Come on Over for Dinner - S7-E23
Continuity mistake: Right after Carlos kills Alejandro with the candlestick, he throws the candlestick to the left of Alejandro's body. But a few seconds later the candlestick has suddenly moved to near Alejandro's head.
Continuity mistake: Lynette climbs on the bed to speak to Tom and is wearing black soled shoes. After they finish talking she is on the bed barefooted. (00:37:34 - 00:38:25)
Continuity mistake: When Mike comes home soon and finds Susan in sexy lingerie in the living room, the laptop reads 0:00:36. Mike grabs Susan in his arms while she desperately tries to shut off the laptop, but only seven seconds later the screen reads 0:06:33. Then the camera switches again and the laptop reads 0:02:47 when Susan finally shuts the screen. (00:14:45)
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.