Complex sentence: On October 8, Alexandra Daddario, Tom Welling and Maggie Grace joined the film, Welling would play lead as Ryan, a doctor at his father's practice who is Gabby's boyfriend, and Grace would play Travis' sister, Stephanie.
Split into simpler sentences: On October 8, Alexandra Daddario, Tom Welling, and Maggie Grace joined the film. Welling plays Ryan, a doctor at his father's practice who is Gabby's boyfriend, and Grace plays Travis' sister, Stephanie.