Congratulations!
With [name_u]Miles[/name_u], I love [name_u]Julian[/name_u], [name_u]Elliot[/name_u], & [name_m]Theodore[/name_m].
Other ideas:
[name_u]Alex[/name_u]
[name_u]Cody[/name_u]
[name_m]Cole[/name_m]
[name_m]Eugene[/name_m]
[name_m]Gage[/name_m]
[name_u]Henry[/name_u]
[name_u]Jack[/name_u]
[name_u]Rhys[/name_u]
[name_u]Rory[/name_u]
[name_m]Sebastian[/name_m]
[name_u]Theo[/name_u]
[name_u]Wesley[/name_u]
[name_u]Wyatt[/name_u]
I think [name_u]Owen[/name_u] is perfect with [name_u]Miles[/name_u], honestly!!
Others I thought of:
[name_u]Owen[/name_u]
[name_u]Arlo[/name_u]
[name_u]Luca[/name_u]
Mile$ Oliv3r andā¦.
[name_m]Jacob[/name_m] [name_u]Thayer[/name_u]
[name_m]Jacob[/name_m] [name_u]Thaddeus[/name_u]
[name_u]Miles[/name_u] and [name_m]Jake[/name_m]
[name_u]Miles[/name_u] and [name_u]Jack[/name_u]
[name_u]Miles[/name_u] and JT
[name_u]Miles[/name_u] [name_m]Oliver[/name_m] would lend itself to [name_m]Malcolm[/name_m] [name_u]Owen[/name_u] (also a great way to include your other sonās choice) as a sibling, though you have to consider if you want something that feels so similar or if youāre totally against it. If youāre totally against it, based on the other names youāve given, Iād say [name_u]Julian[/name_u] [name_m]Theodore[/name_m] because it has the same strong i sound in the first and strong o sound in the second in the same way as your first son.
I know brothers [name_u]Miles[/name_u] and [name_m]Mitchell[/name_m].
Other suggestions [name_u]Miles[/name_u] and
[name_u]Callum[/name_u]
[name_u]Henry[/name_u]
[name_u]Jesse[/name_u]
[name_u]Noah[/name_u]
[name_u]Parker[/name_u]
[name_u]Rhett[/name_u]
[name_m]Roman[/name_m]
[name_u]Tate[/name_u]
I just wanted to thank everyone for their input on this topic. Our son came early and was born this past [name_f]Sunday[/name_f]. I referenced this thread several times while trying to decide and we ultimately chose [name_u]Julian[/name_u]. [name_m]Malcolm[/name_m] was my choice but I was outvoted and Iām fine with that. Iām happy with [name_u]Julian[/name_u].
We have yet to pick a middle name. We may still do [name_u]Julian[/name_u] [name_m]Theodore[/name_m] but a few family members mentioned the rules of not using 3-syllable names for first and middle? News to me. I will admit it did feel odd at times and maybe thatās why. [name_u]Julian[/name_u] [name_u]Theo[/name_u] maybe? Maybe we have to stop putting ourselves in the JT initials box.
Congratulations!! I hope you fall in love with the name and that it suits him. I wouldnāt get too hung up on syllable ārulesā since I like [name_u]Julian[/name_u] [name_m]Theodore[/name_m] but it should feel right. Iāll stick with JT since that would be a lovely tribute.
[name_u]Julian[/name_u] [name_m]Thatcher[/name_m]
[name_u]Julian[/name_u] [name_m]Tobias[/name_m]
[name_u]Julian[/name_u] [name_m]Titus[/name_m]
[name_u]Julian[/name_u] [name_u]Taylor[/name_u]
[name_u]Julian[/name_u] [name_m]Tavish[/name_m] (my personal fave)
And of course [name_u]Julian[/name_u] Toilet Flush 
Phonetically [name_u]Julian[/name_u] is three syllables, but a lot of people pronounce it with two syllables Jule-yen so I would not let the 3 syllables stop me and I have never heard that rule. [name_u]Julian[/name_u] [name_m]Theodore[/name_m] is very handsome.
Congratulations! [name_u]Julian[/name_u] is a great name.
I suppose there might be some sort of informal āruleā to vary syllable count, but [name_u]Julian[/name_u] [name_m]Theodore[/name_m] sounds great to me! [name_u]Or[/name_u] maybe [name_u]Julian[/name_u] [name_m]Malcolm[/name_m]?
[name_u]Julian[/name_u] [name_m]Malcolm[/name_m] I have considered for sure. [name_f]Kinda[/name_f] feels like putting [name_m]Malcolm[/name_m] there is just a consolation prize lol. Itās ok though. Iāve been thinking a lot about [name_u]Julian[/name_u] [name_m]Crews[/name_m]. I like [name_u]Cruz[/name_u] but is it too Spanish sounding considering [name_u]Julian[/name_u] is pronounced Who-Lee-in Spanish speaking countries?
You can see Iām an over thinker 
Yeah, I can totally see that with [name_m]Malcolm[/name_m], ha!
I donāt find that [name_u]Julian[/name_u] [name_u]Cruz[/name_u] is too Spanish. I might suspect he had some Hispanic heritage, but [name_u]David[/name_u] Beckhamās use of [name_u]Cruz[/name_u] in 2005 has anglicized its usage in English-speaking countries, I think. [name_m]Crews[/name_m] is new to me, though I suppose it fits with the āpluralā trend right now (Hayes, [name_u]Brooks[/name_u], [name_u]Rhodes[/name_u], etc.) [name_u]Terry[/name_u] [name_m]Crews[/name_m] is the first person that comes to mind with that spelling. Iāve seen [name_u]Cruise[/name_u] as well, but I find it a bit boat-y.
If I read [name_u]Julian[/name_u] [name_u]Cruz[/name_u], I definitely pronounce it the āhoo-lee-anā pronunciation in my head, like you were thinking is a possibility. If [name_u]Julian[/name_u] is by itself or not with a really Spanish name, I pronounce it Hoo-lee-an. So yeah, I recommend against a Spanish middle name with [name_u]Julian[/name_u]
What about [name_m]Simon[/name_m], if you like [name_m]Sy[/name_m] but [name_m]Silas[/name_m] is too close?
I think [name_u]Julian[/name_u], [name_u]Jude[/name_u] (you could even do [name_u]Julian[/name_u] nn [name_u]Jude[/name_u] if you wanted to use both!) and [name_m]Theodore[/name_m] go best with [name_u]Miles[/name_u] but I do also like your sonās suggestion of [name_u]Owen[/name_u].
Other ideas:
[name_m]Louis[/name_m]
[name_m]Oscar[/name_m]
[name_u]Edward[/name_u]
[name_u]Jonah[/name_u]
[name_u]Henry[/name_u]
[name_m]Graham[/name_m]
[name_m]Grant[/name_m]
[name_f]Edit[/name_f]: [name_m]Just[/name_m] saw the post where your son was born, congratulations! [name_u]Julian[/name_u] is a fantastic choice
Thank you! [name_m]Little[/name_m] guy decided to come a week early! We ended up going with [name_u]Julian[/name_u] [name_m]Malcolm[/name_m] but are strongly considered swapping those so itās [name_m]Malcolm[/name_m] [name_u]Julian[/name_u].
Iām having some regret about the name [name_u]Julian[/name_u]. I donāt know whyā¦I think because of [name_f]Julienne[/name_f], [name_u]Julianne[/name_u], [name_u]Julien[/name_u], [name_m]JuliĆ”n[/name_m], etc. And the nn [name_u]Jules[/name_u] works for all those! I like a name that stands out a little more and [name_m]Malcolm[/name_m] was high on our list.
Him coming a week early when we werenāt settled on a name certainly has added to the stress of naming.
Completely agree with this. [name_u]Cruz[/name_u] sounded cool but after a bit of research I learned [name_m]JuliƔn[/name_m] [name_u]Cruz[/name_u] was a pretty popular Spanish name.