The little critter new baby is good. It has both parents, but it's mostly about what a big brother can do with a new baby - cuddle, let her hold his finger, etc. The parents are sorta on the periphery. Like it says 'dad says we have a new baby and she's coming home today', but then dad sorts disappears.
Little critter has another one about 2 brothers and all the fun they can have when the baby gets older, but I haven't read it so I don't know how involved the parents are.
Good thing about the critter books is they're like $3 on amazon, so not overly expensive if you decide you don't like them. DD really liked the 'new baby' one.
SAHM to Magnolia May (09/10) and Luke Russett (04/13) and wife and best friend to my airman.