Visible crew/equipment: Right before Bree drives herself to the emergency room and is talking to Mrs. McCluskey, a crew member's face is reflected in the car's left wing mirror.
Visible crew/equipment: When Karen McCluskey was stepping from the car when she was taking Bree Van de Kamp to the hospital the crew members appear in the mirror.
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.