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[name]Tamar[/name] [name]Jennifer[/name]
[name]Tamara[/name] [name]Jennifer[/name]
[name]Samara[/name] [name]Jennifer[/name]
[name]Raina[/name] [name]Jennifer[/name]
[name]Calla[/name] [name]Jennifer[/name]
[name]Anya[/name] [name]Jennifer[/name]
[name]Bernadette[/name] [name]Jennifer[/name] (nn [name]Birdie[/name] [name]Jennifer[/name], [name]Betty[/name] [name]Jennifer[/name])
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Okay, so I’m going to bypass most Old Testament names, on the theory that if one of them worked, they would have already found it. But there are tons of classic names that feel compatible with current Old Testament names, and have great meanings, too.
[name]Laura[/name]-[name]Jennifer[/name] - not Biblical, but certainly a classic choice
[name]Lila[/name]-[name]Jennifer[/name]
[name]Emma[/name]-[name]Jennifer[/name]
[name]Lucy[/name]-[name]Jenna[/name]
[name]Lucia[/name]-[name]Jennifer[/name]
[name]Rebecca[/name]-[name]Jen[/name]
[name]Delia[/name]-[name]Jennifer[/name]
Well, seeing as they sort of like [name]Molly[/name], I will base my suggestions off of that:
[name]Sadie[/name]-[name]Jennifer[/name] “[name]Sadie[/name]-[name]Jen[/name]”
[name]Jennifer[/name]-[name]Bethany[/name] “[name]Jennie[/name]-[name]Beth[/name]”
[name]Eden[/name]-[name]Jennifer[/name] “[name]Edie[/name]-[name]Jen[/name]”
[name]Millie[/name]-[name]Jennifer[/name]
[name]Violet[/name]- [name]Jenna[/name]
[name]Amelia[/name]- [name]Jennifer[/name] “[name]Milly[/name]-[name]Jen[/name]”
[name]Emme[/name]-[name]Jennifer[/name]
[name]Eloise[/name]-[name]Jennifer[/name] “[name]Lola[/name]-[name]Jen[/name]”
[name]Lily[/name]-[name]Jenna[/name]
[name]Aurora[/name]-[name]Jenn[/name]
[name]Delilah[/name]-[name]Jennifer[/name] “[name]Lila[/name]-[name]Jen[/name]”
[name]Jennifer[/name]-[name]Eve[/name]
[name]Jennifer[/name]-[name]Lael[/name]
[name]Phoebe[/name]-[name]Jenna[/name]
any of these work?
[name]Jennifer[/name]-[name]Agnes[/name]
[name]Jennifer[/name]-[name]Pearl[/name]
[name]Jennifer[/name]-[name]Lily[/name]
[name]Jennifer[/name]-[name]Blythe[/name]
[name]Jennifer[/name]-[name]Ivy[/name]
Jennifer-Layla
[name]Jenna[/name]-[name]Willow[/name]
[name]Jenna[/name]-[name]Claire[/name]
[name]Jenna[/name]-[name]Carys[/name]
Jenna-Louise
Jenna-Kate
Sabrina-Jen
Willa-Jen
That’s all I can think of now. [name]Hope[/name] this helps!
[name]Chloe[/name]-[name]Jennifer[/name], [name]Chloe[/name]-[name]Jenna[/name], or [name]Chloe[/name]-[name]Jen[/name]? [name]Chloe[/name] has biblical roots and sounds great with [name]Jennifer[/name]/[name]Jen[/name]/[name]Jenna[/name] 
Some of these might work too.
[name]Naomi[/name]-[name]Jenna[/name]
[name]Tabitha[/name]-[name]Jen[/name]
[name]Rebecca[/name]-[name]Jen[/name]
[name]Moriah[/name]-[name]Jennifer[/name]
[name]Jenna[/name]-lee
[name]Jenna[/name]-[name]Lynn[/name]
[name]Farrah[/name]-[name]Jenn[/name]
[name]Jenna[/name]-[name]Fay[/name]
Milena-Jennifer
Makayla-Jenn
Jennifer-Evangeline
[name]Selah[/name]-[name]Jennifer[/name]
[name]Mariah[/name]/[name]Moriah[/name]-[name]Jennifer[/name]
[name]Eden[/name]-[name]Jennifer[/name]
[name]Yael[/name]-[name]Jennifer[/name]
[name]Lydda[/name]-[name]Jennifer[/name] (or [name]Lydia[/name]-[name]Jennifer[/name])
[name]Dinah[/name]-[name]Jennifer[/name]
[name]Seraphina[/name]-[name]Jennifer[/name]
[name]Angelica[/name]-[name]Jennifer[/name]
Are all I’m coming up with, unless they would consider feminizations of Biblical names. Something like:
[name]Petra[/name]-[name]Jennifer[/name]
[name]Paula[/name]-[name]Jennifer[/name]
[name]Simone[/name]-[name]Jennifer[/name]
[name]Gabriella[/name]-[name]Jennifer[/name]
[name]Michaela[/name]-[name]Jennifer[/name]
[name]Dara[/name]-[name]Jennifer[/name]
I really like the suggestions of [name]Chloe[/name]-[name]Jennifer[/name] and [name]Eden[/name]-[name]Jennifer[/name]. I also like the [name]Delilah[/name]-[name]Jennifer[/name] suggested altered to [name]Delilah[/name]-[name]Jen[/name]. While [name]Delilah[/name] was the ultimate bad girl, her name was used even by the puritans.
I also recommend [name]Eve[/name]-[name]Jennifer[/name]. The meaning of [name]Eve[/name] is life, which is a great meaning, and with its shortness, the long double-barrel with [name]Jennifer[/name] doesn’t seem off. I see [name]Jennifer[/name]-[name]Eve[/name] suggested above and I like that too, but the theme seems to be the Biblical name up front, and also [name]Jennifer[/name]-[name]Eve[/name] is sounding closer and closer to [name]Genevieve[/name].
[name]Abigail[/name]-[name]Dawn[/name] and [name]Eve[/name]-[name]Jennifer[/name] seem made for each other.
A few more nice ones in the realm of familiar names:
[name]Esther[/name]-[name]Jen[/name] or [name]Esther[/name]-[name]Jenna[/name], from the old testament [name]Esther[/name].
[name]Claudia[/name]-[name]Jen[/name], [name]Claudia[/name]-[name]Jennifer[/name] (Who is CLAUDIA in the Bible - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Candace[/name]-[name]Jennifer[/name], [name]Candace[/name]-[name]Jenna[/name], [name]Candace[/name]-[name]Jen[/name] (Who is CANDACE? - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Martha[/name]-[name]Jennifer[/name], [name]Martha[/name]-[name]Jen[/name] also has decent flow. [name]Martha[/name] was [name]Mary[/name]'s cousin.
[name]Magdalene[/name]-[name]Jenna[/name] is gorgeous.
[name]Priscilla[/name]-[name]Jen[/name] would also be nice. (Priscilla - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Rhoda[/name]-[name]Jen[/name], [name]Rhoda[/name]-[name]Jennifer[/name] (Rhoda - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Michal[/name]-[name]Jen[/name], [name]Michal[/name]-[name]Jenna[/name], [name]Michal[/name]-[name]Jennifer[/name] (Who is MICHAL? (Mikal) - WebBible Encyclopedia - ChristianAnswers.Net)
More out there, but nice
[name]Persis[/name]-[name]Jen[/name], [name]Persis[/name]-[name]Jenna[/name], [name]Persis[/name]-[name]Jennifer[/name] all work (Persis - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Mahala[/name]-[name]Jen[/name] (preferable variant to [name]Mahalath[/name] or [name]Mahlah[/name]: Who is MAHALATH? - WebBible Encyclopedia - ChristianAnswers.Net; Mahlah - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Talitha[/name]-[name]Jen[/name] (“talitha cumi” is the two word phrase [name]Jesus[/name] says when he resurrects the rabbi’s daughter: “little girl, awake”).
[name]Keziah[/name]-[name]Jen[/name] (Kezia - WebBible Encyclopedia - ChristianAnswers.Net) (variant [name]Cassia[/name]-[name]Jen[/name] would also be nice)
[name]Keturah[/name]-[name]Jen[/name] (Who is KETURAH? - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Milcah[/name]-[name]Jen[/name] or [name]Milcah[/name]-[name]Jennifer[/name] both work (Milcah - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Shifra[/name]-[name]Jen[/name] or [name]Shifra[/name]-[name]Jennifer[/name] (Shiphrah - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Sapphira[/name]-[name]Jen[/name] (another bad girl, but it’s pretty Sapphira - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Sephora[/name]-[name]Jen[/name] (variant of [name]Zipporah[/name]: Who is ZIPPORAH? - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Zipporah[/name]-[name]Jen[/name] (is also nice, and with [name]Abigail[/name] you’d have A-Z: Who is ZIPPORAH? - WebBible Encyclopedia - ChristianAnswers.Net)
[name]Jennifer[/name], with three syllables and strong sounds, will really only work in the first spot, which means it would have to be paired with a short second name. I know these girls are already losing a bit of their identity, but I think using [name]Jenn[/name]/[name]Jenna[/name] will work best.
[name]Bethany[/name]-[name]Jenn[/name]
[name]Charity[/name]-[name]Jenn[/name]
[name]Lydia[/name]-[name]Jenn[/name]
[name]Naomi[/name]-[name]Jenn[/name]
[name]Tabitha[/name]-[name]Jenn[/name]
[name]Jenna[/name]-[name]Grace[/name]
[name]Jenna[/name]-[name]Faith[/name]
[name]Jenna[/name]-[name]Hope[/name]
[name]Jenna[/name]-[name]Sarai[/name]
I think [name]Jenna[/name] + the virtue names seems the most natural.
My immediate thoughts:
[name]Lydia[/name]-[name]Jen[/name]
[name]Mara[/name]-[name]Jen[/name]
[name]Naomi[/name]-[name]Jen[/name]
[name]Bethany[/name]-[name]Jen[/name]
[name]Dinah[/name]-[name]Jen[/name]
[name]Esther[/name]-[name]Jen[/name]
[name]Shiloh[/name]-[name]Jen[/name]
[name]Jenna[/name]-[name]Eve[/name]
[name]Jenna[/name]-[name]Miriam[/name]
[name]Jenna[/name]-[name]Hope[/name]
[name]Jenna[/name]-[name]Faith[/name]
[name]Jenna[/name]-[name]Pearl[/name]
[name]Jen[/name]-[name]Elizabeth[/name]
[name]Jen[/name]-[name]Shiloh[/name]
[name]Jennifer[/name]-[name]Eve[/name]
[name]Jennifer[/name]-[name]Selah[/name]
[name]Jennifer[/name]-[name]Pearl[/name]
I think [name]Naomi[/name]-[name]Jen[/name], [name]Mara[/name]-[name]Jen[/name], and [name]Lydia[/name]-[name]Jen[/name] are my faves out of these, and I think [name]Jen[/name] in the second place makes it less overwhelming than a full on double barrel including [name]Jennifer[/name]. These girls will already have alot to acclimate to with out a six syllable name, KWIM?
ETA: Nice suggestions @blade I took too long saving my post and posted to see we had many of the same suggestions. I see your point about the [name]Jenna[/name]+virtue names, it does seem very natural to say and less forced than some of the others.
I have to disagree in part with @blade. While I do think the flow is a little clunky with [name]Jennifer[/name] in the second spot, it can work.
[name]Sarah[/name] [name]Jessica[/name] [name]Parker[/name] has made her double barreled first work, and [name]Jessica[/name] and [name]Jennifer[/name] take an equal amount of time to say.
I was actually thinking [name]Grace[/name]-[name]Jennifer[/name], [name]Faith[/name]-[name]Jennifer[/name], and [name]Hope[/name]-[name]Jennifer[/name] all work. Especially [name]Grace[/name]: [name]Gracie[/name]-[name]Jen[/name] as a nn.
The time-of-day connection between [name]Abigail[/name]-[name]Dawn[/name] and [name]Eve[/name]-[name]Jennifer[/name] just hit me too. I think it’s nice, and I also think it’s less blatant than making it [name]Abigail[/name]-[name]Dawn[/name] and [name]Jennifer[/name]-[name]Eve[/name].
Another thought: much as [name]Lily[/name]-[name]Jennifer[/name] was suggested due to the symbolism of lilies, [name]Olive[/name] etc would work in the same way.
[name]Olive[/name]-[name]Jennifer[/name], [name]Olive[/name]-[name]Jenna[/name], [name]Olivia[/name]-[name]Jen[/name].
and how could we forget: [name]Christa[/name]-[name]Jennifer[/name], [name]Christa[/name]-[name]Jen[/name], [name]Christine[/name]-[name]Jenna[/name], [name]Christine[/name]-[name]Jennifer[/name], [name]Christina[/name]-[name]Jen[/name], [name]Christiana[/name]-[name]Jen[/name].
Corinthia-[name]Jen[/name]?
Out of curiosity, do the girls go by their English names primarily, or the Chinese? I think I’d feel more comfortable shortening Jennifer if it’s not even what they typically answer to.
ETA: Nevermind. I missed where you said that they currently go by the English name.
[name]Hannah[/name]-[name]Jen[/name]
[name]Jennifer[/name] [name]Merry[/name]
[name]Jenna[/name]-[name]Noelle[/name]
[name]Jennifer[/name]-[name]Anne[/name] nn [name]Jenna[/name]
[name]Anna[/name] [name]Jennifer[/name]
[name]Gloria[/name]-[name]Jen[/name]
I really like the virtue name suggestions ([name]Hope[/name], [name]Grace[/name], [name]Blythe[/name], [name]Felicity[/name], [name]Amity[/name], etc).
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[name]Cecilia[/name]-[name]Jen[/name]
[name]Emily[/name]-[name]Jen[/name]/[name]Emily[/name]-[name]Jennifer[/name]
[name]Mia[/name]-[name]Jenna[/name]/[name]Mia[/name]-[name]Jennifer[/name]
[name]Madeleine[/name]-[name]Jen[/name]
[name]Mariah[/name]-[name]Jen[/name]/[name]Mariah[/name]-[name]Jennifer[/name]
[name]Chana[/name]-[name]Jen[/name] ([name]Chana[/name] means favor/grace)
Hosanna-[name]Jen[/name] (Hosanna means deliver us)
[name]Salome[/name]-[name]Jenna[/name]/[name]Jenna[/name]-[name]Salome[/name] ([name]Salome[/name] means peaceful)
Too bad A’s and J’s are out. My 2 favorites would be [name]Jennifer[/name]-[name]Jael[/name] and [name]Ada[/name]-[name]Jen[/name]/[name]Ada[/name]-[name]Jennifer[/name].
Im still voting for [name]Sadie[/name]-[name]Jennifer[/name]! [name]Sadie[/name] as a diminutive of [name]Sarah[/name], which is Hebrew from princess - not a bad meaning at all!
If they liked [name]Willow[/name], they might like [name]Marlowe[/name]? [name]Marlowe[/name]-[name]Jenna[/name] maybe? Not the best meaning (driftwood), but the flow of the name is great.
If they liked [name]Laura[/name], then what about [name]Laurel[/name]? [name]Jenna[/name]-[name]Laurel[/name] is pretty, and the meaning of [name]Laurel[/name] is “[name]Laurel[/name] tree”. The laurel is also a key component in Greek Mythology, where a laurel wreath is used as a marker of victory. ([name]Jenna[/name]-[name]Lorelei[/name] could also be an option, but if meaning is super important to them, it is less than ideal)
[name]How[/name] about [name]Jennifer[/name]-[name]Claire[/name]? Or [name]Clara[/name]-[name]Jennifer[/name]? Their meaning is “bright, clean and pure” which is nice, and [name]Claire[/name]/[name]Clara[/name] & [name]Abigail[/name] make a fantastic sib-set.
[name]Victoria[/name]-[name]Jenn[/name] (meaning ‘victory’)
[name]Ella[/name]-[name]Jennifer[/name] (meaning 'goddess" in Hebrew)
[name]Matilda[/name]-[name]Jenn[/name] (meaning ‘mighty in battle’)
[name]Lucy[/name]-[name]Jennifer[/name] (meaning “light”)
thats all i have for now!