Panel 1: After Elly slumps off in despair because her horrible child just did to her the same thing she did to Marian, Mike tells the person he's talking to on the phone that his parents are always on his case and that he can't do anything without getting yelled at for something.
Panel 2: He goes on to say that all day at school, he has to do things other people want him to do like his opinion can't matter and the second he gets home, it's endless lecturing about doing stuff he doesn't see the need to do. He starts off setting up the stupid Aaron-shaming punchline by saying that he's telling this person something.
Panel 3: As we zoom out to him sitting on the chair making a mess for Elly to clean up, we see her react to his comment about how his life is one big hassle by going into full-on deer in headlights mode.
Summary: Mike might be a bit of a couch potato but, despite what Lynn might believe, his relaxing and talking on the phone doesn't invalidate his feelings that Elly and John envy him his youth and freedom and seek to destroy his ability to do something they cannot: enjoying life. His belief that his parents hate laughter and a happiness no grown-up can really feel collides messily with Elly's belief that everyone but her is having a fabulous time at her expense.