We are pretty set on [name_m]Ambrose[/name_m] if baby 3 is a boy. The best nickname we can think of is [name_m]Oz[/name_m], which dh really wanted as a name anyway. But I thought I’d put it out there in case you all come up with a better option 
Another question: is [name_f]Rose[/name_f] or [name_f]Rosie[/name_f] really off limits for a boy?
[name_u]Love[/name_u] [name_m]Ambrose[/name_m].
I would opt for [name_m]Ross[/name_m] over [name_f]Rose[/name_f] or [name_f]Rosie[/name_f] for a boy. I think [name_u]Bo[/name_u] would be a viable nickname choice! If dh loves [name_m]Oz[/name_m] that sounds like the winner though.
What about brose?
What is the middle name??? Maybe you could do initials [name_m]Ambrose[/name_m] [name_m]Becket[/name_m]. A.B ( [name_u]Abey[/name_u]) or [name_m]Ambrose[/name_m] [name_u]James[/name_u] A.J or [name_m]Ambrose[/name_m] [name_m]Christopher[/name_m] A.C ( reminde meof saved by the bell… A.C slater! lol)
I agree that initials would be a great nickname for [name_m]Ambrose[/name_m]. [name_m]Oz[/name_m] can work; I don’t think it’s an obvious one, but it makes sense when presented. I know someone whose son is [name_m]Ambrose[/name_m] and his nicknames include Brose, Boz, and AP (his initials). I think [name_f]Rose[/name_f] is pretty exclusively girl, so I would take that one off the table.
Wouldn’t [name_u]Bo[/name_u]/[name_m]Beau[/name_m] work? [name_m]Oz[/name_m] is cute tho! so original
I think [name_m]Abe[/name_m] would make a good nick name! Or Bro? lol Maybe not Bro until he’s in high school.
I like [name_m]Moe[/name_m] or [name_u]Bo[/name_u]
Oh, [name_f]Rose[/name_f] is so off limits! He might turn into a flower if you call him [name_f]Rose[/name_f]! Or even worse… a girl!!
Okay, done with the sarcasm. I like the initials idea. Or [name_u]Bo[/name_u]. You could even use [name_f]Rose[/name_f] if you wanted. Personally I wouldn’t use a nickname for [name_m]Ambrose[/name_m]. It’s only two syllables.
I actually think there is something about a boy named [name_f]Rose[/name_f]. However, I guess [name_m]Ambrose[/name_m] can do without a nickname, it’s not that long.
I would think [name_u]Bo[/name_u] or [name_m]Ross[/name_m]…and can I just say that I think [name_m]Ambrose[/name_m] is a fabulous name? I know my hubby would never let me get away with it, but I just love it.
I could never think of good ones. But I think [name_f]Rosey[/name_f] is fine, I have seen and heard it one men before. Nothing wrong with it at all!
I love [name_m]Ambrose[/name_m] nn [name_u]Bo[/name_u]! Great choice 
I like [name_u]Bo[/name_u] as a nickname for [name_m]Ambrose[/name_m]. I also thought of [name_m]Brody[/name_m] as nickname. [name_m]Oz[/name_m] is pretty cool too!
Ambie
[name_m]Ozzy[/name_m]
[name_f]Posey[/name_f]
[name_f]Rose[/name_f]
Brose
[name_f]Ammy[/name_f]
[name_m]Manny[/name_m]
Ambro
[name_m]Boaz[/name_m] / [name_u]Bo[/name_u]
[name_u]Mo[/name_u]
[name_m]Amos[/name_m] (a stretch?)
?
Good luck! [name_u]Love[/name_u] the nn [name_m]Oz[/name_m], and also second the suggestion of [name_m]Brody[/name_m].
It doesn’t need one