Brother for [name]Zachary[/name] [name]Joseph[/name] and [name]Theodore[/name] [name]Iain[/name]? All sugestions welcome would prefer a name that cannot be shortened and not too common. I like [name]Otis[/name] [name]James[/name] or Wilf [name]James[/name] but not 100% sure!
I think [name]Otis[/name] [name]James[/name] is nice! I don’t really get Wilf, though…that seems very odd to me.
Some other names that don’t lend themselves to being shortened (though, some are more common than others) and would go with your other sons:
[name]Milo[/name]
[name]Miles[/name]
[name]Alastair[/name]
[name]Asher[/name]
[name]Byron[/name]
[name]Darren[/name]
[name]Damian[/name]
[name]Leo[/name] (though maybe it’s too rhymey with [name]Theodore[/name]/[name]Theo[/name])
[name]Callum[/name]
[name]Nigel[/name]
[name]Noel[/name]
[name]Nathan[/name]
[name]Otis[/name] [name]James[/name] is super cute! Use it!
I like [name]Otis[/name] [name]James[/name] best from your choices. Did you mean [name]Wolf[/name] or [name]Will[/name] [name]James[/name] for your other choice?
Some others that sound nice are
[name]Bram[/name] [name]James[/name]
[name]Otto[/name] [name]James[/name]
[name]Micah[/name] [name]James[/name]
[name]Liam[/name] [name]James[/name]
Wilf? As in a nn for [name]Wilfred[/name]? meh
[name]Otis[/name] isn’t my thing either, but it’s better than Wilf. Did you mean [name]Wolf[/name]? I don’t really like that either, sorry.
[name]Zachary[/name] and [name]Theodore[/name] can be shortened. Short, one syllable names are cool though, so here are some suggestions:
[name]Flynn[/name]
[name]Finn[/name]
[name]Cole[/name]/[name]Kole[/name]/Kol
[name]Hale[/name]
[name]Hayes[/name]
[name]John[/name]
[name]Luke[/name]
[name]Jude[/name]
[name]Ford[/name]
[name]Taft[/name]
[name]Tate[/name]
[name]Vaughn[/name] - my FIL’s name was [name]Vaughn[/name] [name]James[/name]. I love his name!
You kind of have a Presidential theme going there. 
Would you consider [name]James[/name] as a first name?
Maybe you would like something from this Classics list: (both of your son’s names are there)
Best of luck!
I like [name]Otis[/name]. Other short names that aren’t to common -
[name]Jude[/name]
[name]Owen[/name]
[name]Arlo[/name]
[name]Finn[/name]
[name]Milo[/name] or [name]Miles[/name]
[name]Fred[/name]
[name]Noah[/name]
[name]Felix[/name]
[name]Hugh[/name] or [name]Hugo[/name]
Good luck
[name]Otis[/name] [name]James[/name]! It works well with brothers [name]Zachary[/name] and [name]Theodore[/name].
I think [name]Otis[/name] sounds dowdy and fusty next to [name]Zachary[/name] and [name]Theodore[/name], which are much grander. Something nickname-proof:
[name]Aaron[/name]
[name]Bryant[/name]
[name]Dawson[/name]
[name]Elliot[/name]
[name]Owen[/name]
[name]Ronan[/name]
[name]Simon[/name]
[name]Ulysses[/name] (presidential!)
[name]Walker[/name]
[name]Lincoln[/name] (presidential)
lucylu, I love [name]Zachary[/name] and [name]Theodore[/name], but as blade said, those names seem grander. I second blade’s suggestions of [name]Elliott[/name], [name]Dawson[/name] and [name]Simon[/name].
[name]Beck[/name] is my fav short name…not too common and easy to pronounce
[name]Finn[/name] - strong but gentle Gaelic name - fair one