J.K.
Depends on how many people you intend to invite, and the ages of the other kids. If some of the kids are older, you may enjoy going to the park where the kids can run more, and are not so confined to the yard. You also may want to think, will your guests be going inside your friends house, to use the restroom? I wouldn't be very comfortable with that, unless everyone knows everyone. And if you are going to, say, bbq food, it might be easier at your friends house so you don't have to carry so much stuff to the park, plus the baby and all her stuff too. Whatever you decide, hope you have a great time!! Happy 1st Birthday to your daughter!