In the episode Peter and his friends Glenn, Cleveland and Joe go over to the drunken clam as they are talking about if they were millionaires what would they spend the money on and as they talk Quagmire spots a girl at the end of the bar starts talking with her and begin saying that if she was lucky to hock up with him she would not remember what happened as soon he said that he boyfriend comes over and tells him to move or get beat up by him and so as Glenn leaves Peter then looks at the women who is sat down with her boyfriend as he looks closes at her, Joe asks peter as if he has seen a ghost and peter is then telling joe that the women looks like him but can not remember where.
Lois and Brian are talking over about looking for a job for her as she is not moving around as much as meg is applying for college, Chris is dating Roberta Tubbs who is the step-daughter to Cleveland and Stewie has now started school, and with peter working a lot and hanging around with the guys, brain thinks if Lois should work as a house keeper and Lois agrees to that as then peter works in drunk and saying that he slept outside thinking that the grass was his bed and then clasped who he then letter falls a sleep on the floor. Lois then hears the front door bell ring as she gets up and then opens to see a young women stand outside and asks if peter was in and the Lois shouts as he then starts walking on his hands by trying to get up and as he gets up he then sees the women from last night and she then asks him if he is peter griffin who he then says that he is peter griffin. The women is over joyed as she tells him that peter is her father in which he thinks is a joke but letter is given a note by her mother who has remarried, in which it tells him that she is his is daughter and Lois then asks peter if he had slept with another women and he then says he slept with another women before he met Lois in which she calms down and welcomes Leanna to the Griffin family and is then asking Lois if her boyfriend could come over to meet them in which Lois wouldn't mind as she is making dinner before the door opens and with Meg and Chris fighting in which who is right for finding money that somebody had dropped forgot to pick it up in which they are greeted by Leanna as then tells them that she is the half-sister.
Stewie comes home after he had won for designing a new school logo for his school and tells Brain who is then asked who the women is and Leanna turns around and is then hugging Stewie in which he is then told by Lois that she is his half-sister and looks more better then meg, Leanna's boyfriend Andrew Paul Smith III, comes in and goes over to her and is then meet by the griffins and he then shakes peter's hand every hard and begins to tell them as they are sat eating and tells them that he works for the CIA after his father retired and his mother passed away and with his older siblings moving out to live with they family's and tells them that he is named after great-great-great-great-great-grandfather Andrew Paul Smith II who had thought in the war against England and Spain and is then sent to america after the British thought he had started to work for the Spanish. Peter asks Andrew if he would like to go to the clam in which he and peter go and Lois is getting ready to go to her first house.