Well, the baby's tolerance will be pretty low so I'd go with a low ABV session beer.
Seriously though, brew whatever type you want, since the baby will be arriving in the summer maybe do a wheat beer or a kolsch since they're lighter bodied and good in hot weather. And, there's no problem with brewing now and letting them age until july/august, actually many styles benefit from some aging
Knucklehead Brewery, Est. 2007
Always do sober what you do drunk. That will teach you to keep your mouth shut. -Ernest Hemingway