I know you feel bad for her...but this idiot will probably keep a female pup from the litter (the kids will want one)....they will grow tired of it by summer...then the new pup will be chained up and probably bred with her sire.
The whole problem will keep on going.
I would make a formal complaint to animal control...there must be some law that puppies must be inside at this time of year??? You could offer to take the mother dog if he cannot care for her....but don't start offering him money.
Gina