Panel 1: We start things off with Elly looking at the window and whining that she thought that Mike and Liz were old enough to be trusted. This is a rather sinister joke because Elly has raised them to be destructive idiots who can't resolve conflict without resorting to violence and name calling.
Panel 2: Elly is forced to endure meaningless buzzing noises about things that both children do actually know mean nothing but pretend they do to bust her ass and ruin her life: Mike's noises sound a lot like 'she locked me out' while you'd swear Liz was saying 'he called me names.'
Liz should have gone on to say that he pounded on the door like an escaped mental patient, cursed like a merchant marine and threatened to perform a living autopsy on her....even if she does know that Elly wouldn't listen because all she cares about is her own immediate need to make a big show of not being in the presence of children.
Panel 3: This is why she redirects the conversation in the manner that is mete and proper and tells them about how she is affected. She is working full time now and cannot be there to supervise. What is she to do? Install short-circuit television?
Panel 4: She is gobsmacked when Mike says that's a good idea and Liz says to keep the cameras outta the biffy. She would be even more gobsmacked if Liz and Mike were to ask "Don't you mean closed-circuit television?"
Summary: As John Jamele said last Monday, if John and Elly had thought ahead and planned out the kids' summer in advance, this would not have happened. Too bad that Elly thinks that even the elementary precaution of saying "If you forget your house key again and I'm working, go to Lawrence's house" means capitulating to Mike and being his slave or some such stupid shit like that.