I don’t think it matters, as long as you choose a name you love, and one that suits him. I’m a firm believer in waiting to see the baby before you make the final decision.
My parents had names all picked for my sister and I, but when our baby sister arrived they rejected the name they had chosen for her (Rachel) and chose Lucy instead. Apparently she screwed up her face and yelled every time they said “Rachel”, which was taken as a fairly good sign she wanted to be called something else.
Perhaps a middle name (if you do middle names) with an R?
Rory (or Ruari, or Ruadhri, depending how Irish you want to make it) is one of my favourite boy’s names, but apparently Americans are turning it into a girl’s name as well.
James (Jamie)
Jacob (Jake)
Daniel (Danny, Dan)
Michael (Mikey, Mickey, Mike, Mick)
Patrick (Paddy, Pat)
Joseph (Joey, Joe)
Samuel (Sam, Sammy)
Brian (Bry)
Jonathan (Jon, Jonny)
Matthew (Matt, Matty)
All give you obvious nicknames to fit in with your other sons.
I love Irish names for boys, but I doubt you’d get away with most of them in the USA.The easiest to pronounce and spell are probably ones like Cormac, Lorcan, Declan, Dermot, Ailill, Colm, Sean and Ciaran.
It all gets a bit difficult when you move over into names like Caomhan (Kwee-Von) and Donncha (Don-ack-uh…sort-of).