Visible crew/equipment: In one of the episodes, Gabby has her Maserati car taken from her by the repo guy. When he pulls off, the car is towed behind him. Clearly reflected in the metallic paint of the Maserati is the crew, with boom, camera and everything else.
Visible crew/equipment: Just before the fire starts you can see a crew member's legs/feet on the right side of the couch. (00:38:06)
Visible crew/equipment: When Susan sits on the couch in Edie's house, just after she throws the bra behind her and knocks the candles over, a crew member in blue jeans can be seen moving on the floor behind the couch to the right.
Visible crew/equipment: When Bree is watering the flowers in the bathroom at the hospital, a shadow of the cameraman is visible behind her.
Running to Stand Still - S1-E6
Visible crew/equipment: When Susan is following Paul in the car she borrowed, we can see the reflection of a crew member on the right hand side of the window. (00:18:15)
Your Fault - S1-E13
Visible crew/equipment: After the scene where Mr and Mrs Rowland speak with Gabrielle, a crew member is reflected on the side of Paul Young's car as he pulls into his driveway with Zach.
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.