I agree, I would go with [name_m]Caleb[/name_m] so you don’t have two B’s. [name_m]Both[/name_m] choices sound good with [name_m]Alexander[/name_m] though.
[name_m]Caleb[/name_m] [name_m]Alexander[/name_m] fit better with your boys. I’m not sure about [name_m]Alexander[/name_m] because it’s another ‘[name_m]Al[/name_m]’ name. What about [name_m]Lysander[/name_m]?
I like [name_m]Caleb[/name_m] best with your other sons’ names. [name_m]Brody[/name_m] seems a bit trendy and nicknamey in comparison to the strong and classic [name_m]Anthony[/name_m] “AJ” and [name_m]Benjamin[/name_m]. Other suggestions would be…
and I like apollonia’s suggestions of [name_m]Nathaniel[/name_m], [name_m]Nicholas[/name_m] & [name_m]Theodore[/name_m] (nicknamed [name_u]Theo[/name_u]).