congrats on the little guy(and the bike too)!
solid tires on that one im guessing? if so you might not be able to get them off in one piece......but id try leaving them in direct sunlight on a hot day for a few hours and then try rolling them off(works sometimes sometimes not)the side......or you couls soak them in boiling water and try rolling them off afterwards*CAUTION*(YOUR GIRL MAY KILL YOU IF YOU DO IT IN THE SINK OR TUB!!!)what i did with my sons pixie was just order some cheap chrome rims(so he wouldnt be stuck on a fixie with solids)and just leave the originals on the stock wheels and swap them back if its ever sold.....