Poppy Marshall is the daughter of Haley and Dylan. She is first mentioned in "Did the Chicken Cross the Road?" when Haley learns that she is pregnant after an accident that brings her to the emergency room. A nurse reveals her and Dylan the surprising news after a routine test. In "A Moving Day" Haley and Dylan have their first ultrasound and find out that they're having twins.
The twins are born in "A Year of Birthdays".
- Since the twins were presumably conceived close to the end of Haley's relationship with Arvin Fennerman and the beginning of her renewed relationship with Dylan, there was a possibility of either of them being the father. However, in "Kids These Days" Haley confirms that she thinks Dylan is the father.
- In "A Year of Birthdays", shortly after the twins are born, Claire jokingly implies that Haley would have named them Pixar and Coachella if she named while when still on the painkiller drugs from the birth.