Every Day a Little Death - S1-E12
Continuity mistake: When Edie throws the urn of ashes at Susan after she discovered Susan burned her house down, you can see that there is nothing on Edie's left shoulder, but when the camera angle changes to behind Edie in the next shot, her shoulder is now covered by her cardigan.
Continuity mistake: When Lynette introduces herself to Claire at the park, the strap on her handbag is on her shoulder. When the camera angle changes to behind Lynette in the next shot, the strap has gone, and in the shot after that, it is back again.
Every Day a Little Death - S1-E12
Continuity mistake: When Edie throws the container of Mrs Huber's ashes over Susan after she discovered Susan burned her house down, there is still some ash in Susan's hair and on her cardigan from a previous take.
Continuity mistake: When Zach is in Julie's bedroom, he says to her, "And they buried her, to protect me" and you can see that Zach has his hand on his cheek. When the camera angle changes to behind Zach in the next shot, he no longer does.
Continuity mistake: Before the fight between Helen and Susan at the fashion show, Susan has a flower in her hair. There is no sign of the flower when Helen tears off part of her wedding dress, but when Susan says "What?", the flower is back again.
Every Day a Little Death - S1-E12
Continuity mistake: When Edie is about to spray water on Susan from the hose, you can see that Susan is very close to Edie, but as the camera angle changes she is much further away.
Continuity mistake: At the start of the episode, Zach picks up some gravel from beneath the lamppost and throws it at Julie's window. But when he leaves Susan the flowers, you can see that the gravel has disappeared.
Continuity mistake: When Bree is preparing a care package to ship to Andrew's camp, she sneaks some lemon bars into the package, and quickly closes the two side flaps of the cardboard box, leaving the end flaps out. In the next shot, she is immediately taping the box with all flaps down.
Continuity mistake: Parker is tearing the flowers apart until there are none. In the next shot, there are some flowers left, and when he jumps off the chair, the flowers have gone again.
Love Is in the Air (a.k.a. What I Did for Love) - S1-E14
Continuity mistake: When Gabrielle is putting the lipstick on Yao Lin in the department store, the lipstick changes between shots.
Love Is in the Air (a.k.a. What I Did for Love) - S1-E14
Continuity mistake: When Gabrielle is speaking to Mickey on the phone, she puts her earrings in a bowl but later on in the scene they are back on her ears.
Every Day a Little Death - S1-E12
Continuity mistake: When Lynette signs the clipboard at yoga, a close-up shows her signing it with her right hand, but in the next shot she is holding Penny with her right hand and signing her name with her left.
Every Day a Little Death - S1-E12
Continuity mistake: When Gabrielle toasts to Carlos' return, the volume of champagne in her glass changes between shots.
Continuity mistake: When Lynette is at the school, the teacher is waiting outside eating. If you look at her hands, you can see that she has a white napkin. The napkin changes from one hand to the other between shots, and in one shot it is small and the other it is not.
Continuity mistake: When John is speaking to Susan about his relationship with Gabrielle, Susan puts her hand on John's cheek, but in the next shot, when John's mother is looking out of her car, Susan can be seen with her hand on John's shoulder.
Continuity mistake: When Bree steals Mary Alice's tape in Dr Goldstein's room, she takes it with her right hand and grabs it to her waist while she raises her left hand to her hair. In the next shot when the doctor enters the room, you can see her right hand is up, and when the camera comes on her the next shot, her left hand is up again.
Continuity mistake: In the scene where Bree and Lynette are talking about nannies, Lynette is in the back seat strapping her baby daughter into the car seat. In the shot facing Bree, Lynette takes a baby toy lying on the back seat and hands it to her daughter, but in the next shot facing Bree, the toy is back on top of the seat where again Lynette hands it to her baby.
Sunday in the Park with George - S1-E21
Continuity mistake: When Bree is out for dinner with George, the scene starts with a close up of her eating with her fork in her right hand. It then cuts to a wide shot of her suddenly holding her fork in her left hand, and then she switches it to her right hand.
Continuity mistake: When Bree is talking to Mike in hospital, the position of her roll neck jumper on her right shoulder changes constantly throughout the scene. In some shots it's rolled down, in some it is rolled up.
Continuity mistake: At one point in episode 1.2 ("Ah, But Underneath"), Susan looks at the note used to blackmail Mary Alice and we can see that it has been folded twice and become somewhat crumpled. Two episodes later in "Who's That Woman?" (1.4) when the girls show the note to Paul, it is almost perfectly smooth with a single horizontal crease.
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.