Ben panics once he realizes he forgot his mom's birthday yet again, especially since he promised her a big blowout after last year's disaster. Knowing he has a lot to make up for, Ben enlists an unwilling Danny, Tucker and Riley to quickly organize the festivities. But when Danny learns something unexpected about his own birthday, Bonnie's party takes on a new twist. Meanwhile, Emma hurts herself on Riley and Tucker's watch, prompting them to become more concerned with hiding her injury than working on Bonnie's video tribute.

Baby Daddy follows Ben, a young man in his early 20s living the life of a bachelor in New York City with his buddy, Tucker, and his brother, Danny. Their lives are turned upside down when they come home one day to find a baby girl left on the doorstep by an ex-girlfriend of Ben's. After much deliberation, Ben decides to raise the baby with the help of his friends and his protective and sometimes over-bearing mother, Bonnie, and his close female friend, Riley.