[3][4] George Venturi (John Ralston), a divorced man from London, Ontario who had custody of his three children from a previous marriage: sons Derek (Michael Seater) and Edwin (Daniel Magder), and daughter Marti (Ariel Waller), marries a divorced woman named Nora McDonald (Joy Tanner), who has two daughters of her own from a previous marriage: Casey (Ashley Leggat) and Lizzie (Jordan Todosey).

Growing up as the oldest child in a household in Toronto with only her mother and sister had suited her well and brought her up as a self-sufficient and independent young woman.

[citation needed] Life with Derek and another Canadian sitcom, Naturally, Sadie, were both added to Disney Channel in the United States in 2005.

[16][deprecated source] The synopsis teased that Casey is now a married lawyer with three kids, while Derek is a successful musician who is also a single dad of one daughter.

[17] Actors Jordan Todosey and Danny Magder, who played Casey's sister Lizzie and Derek's brother Edwin, won't be rejoining the cast.

According to WildBrain Television, the actors are not reprising their younger sibling roles due to "scheduling challenges"; Todosey claimed she was not contacted.