Danny and Ben are eager to find out the sex of Riley and Danny’s baby, even though Riley would prefer it to be a surprise. In their quest to find the truth, the brothers create a chain reaction of mix-ups. Meanwhile, Riley fights for Brad’s innocence in his final trial, and Tucker auditions to be in a new courtroom reality series.
When Ben believes he finally has found a no-strings-attached hookup buddy, Riley attempts to prove to him he’s sorely mistaken. Meanwhile, Danny ends up in a professional wrestling match.
Ben learns some interesting facts about Tucker’s recent date, so he enlists Danny’s help in finding out the truth. As Bonnie and Brad are preparing to set off on their trip around the world, Brad is arrested by the FBI.
Ben is still enthusiastically searching for the mysterious Elle. Danny and Riley are hunting for a good doctor to help with the pregnancy, and Bonnie desperately wants to be involved. Tucker is back from Los Angeles, but refuses to tell anyone what happened while he was there.
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.