Continuity mistake: When Mrs McCluskey is talking to her sister on the coach, she has a plate of food in her left hand and some papers in her right. When Roberta rips the papers out of her hands, the plate of food is gone and is replaced by a sandwich.
Continuity mistake: When Lynette gets up from the PTA meeting to go to the washroom, she has a purse on her shoulder. After her confrontation with Anne Schilling, Lynette storms out of the washroom but she is no longer carrying her purse.
Mama Spent Money When She Had None - S5-E14
Continuity mistake: In an early scene Bree pulls up in a Lexus four door and the camera lingers on the car. But later in this episode she brings the same car home as a gift for herself.
Bargaining - S5-E21
Continuity mistake: When Juanita rushes down the stairs and goes outside the door, you can see that Gaby is holding a plate of leftover food in her left hand, but in the next shot the plate has suddenly changed into a bowl.
Bargaining - S5-E21
Continuity mistake: During the breakfast scene with Mike, Katherine and MJ at the start of the episode, the spoon in MJ's bowl of oatmeal changes position between shots.
Answer: Kayla was sent away in episode 16 (The Gun Song) in season 4, after falsely accusing Lynette of child abuse. She now lives with her grandparents - probably Nora's parents.
I'm curious why we never see her again, why she never talked about, and why Tom never mentions visiting her.