Hi berries,
Please vote for your favourite from my top 15 girl names! Sister for PJ (Penelope James). Middle name TBD, last name M@cKimmie.
Note: She almost never goes by Penelope! So matching with PJ is priority.
Thank you
I love [name_f]Penelope[/name_f] and [name_f]Clementine[/name_f] as sisters! [name_f]Beatrix[/name_f] was a close second 
ooh, this was tricky! I really like the idea of PJ and [name_m]Murphy[/name_m] [name_f][/name_f]- so charming and sparky!
[name_f][/name_f]I was also considering voting for [name_f]Goldie[/name_f], [name_m]Frankie[/name_m], [name_f]Billie[/name_f], and [name_f]Lucille[/name_f] ‘Lulu’/‘Lucky’!
[name_f]Clementine[/name_f] is gorgeous as sister to Penel0pe Jam3s!
My two factors were - match with PJ but more important match (and good flow to) your last name.
I like these names but I don’t think they go with your last name: Summer, Billie, Clementine/Lemmie, Frankie, or Esme - all too much of a mouthful and/or too fast paced.
I went for Lucille as the pace goes so well with last name. I think Lucky is so sweet and I also like the simple and elegant, Lil.
I also really like Murphy - but with a very feminine middle to balance.
Matilda is good but I think Tilda goes better than Tillie with last name (though obv flow from a nickname not as important).
Also, if want Clementine (still think tricky with last name) then Cleo as a nn or even Minnie - obv Minnie rhymes but still easier than Lemmie with last name (though see above re nicknames).
I’d also suggest Bridget nn Birdie, or Willamina nn Billie, so both have a long & “proper” name. Same for Frankie - would use Frances or Francesca so broadly equitable - I wouldn’t want to be Ozzy or Stevie or a nickname name if my sister were Penelope (and I think Ozzy and Stevie won’t age well as full first names). I prefer Francy or Franny to Frankie (it’s quite harsh incl with your last name) but obv take or leave, as with all.
Other options:
Josephine - Josie
Cecily - Cessie, Cece
Eloise - Lola, Lulu, Elle, Lois
Florence - Florrie, Flo, Ren
Margot - Mimi (two M name)
Beatrice - nn Birdie - flows more smoothly imo to MacK.
[name_f]Dorothy[/name_f], [name_f]Goldie[/name_f], [name_f]Birdie[/name_f] were my favorites 
I love [name_m]Ozzy[/name_m] with PJ! I also love [name_f]Goldie[/name_f], [name_m]Frankie[/name_m] and [name_f]Stevie[/name_f] from your list
Congratulations! I’m excited that PJ is getting a sister!
Personally I really like the boyish nicknames like Stevie, Billie, Frankie with PJ — even though you don’t use her full name, they do go nicely stylistically with big sis’ androgynous middle and nickname.
Also love Lucille/Lucky/Lulu for you — it’s fabulous with your surname and big sister’s name in all its iterations 