If you LOVE Zachary then use it. My brother and cousin have the same name, we saw them a lot growing up and it was never a big deal. If you're worried maybe chat to you BIL/SIL about it.
Oliver is very popular atm.
Gabriel is a bit femine for me.
Love Wilder, very cool, bit differnt.
Zachary/Isaac - I agree with Junglemum, if you love Zachary, then use it. If Isaac gets called Zac, maybe call Zachary "Zacky" (IYKWIM?)
Oliver - I looove this name
Gabriel - This was one of the names on our list for a little bit when I was pregnant, but looking at it again I don't really like it anymore.
Wilder - Nope. You asked for brutal, so I don't feel too bad at saying that I hate this name. Wil, yes, that's nice, but not Wilder. Sorry
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