I wash all of my quilts before I gift them (I'm a glue-baster so it's not optional), and baby quilts I
always wash in HOT water, to make sure they can handle it. I just assume that at some point the quilt will suffer an "accident" and need the hot wash anyway, so I do it first and that way I can tell the parents that the quilt is hot-wash approved.
I have NEVER had a quilt fail due to hot water! I usually pre-wash my fabrics so I already know if something is a bleeder (in fact if I know a fabric is destined for a baby quilt I'll pre-wash in hot too) but sometimes I use precuts and those don't get pre-washed. If you haven't started yet, maybe do a thorough pre-washing; but either way, I think a couple of color catchers in the wash and you'll be FINE.
Congrats on the new granddaughters!!