Mason blows away Cooper in spelling battle as the kid preps for a big bee. It's troubling how bad Coop is when it comes to spelling, but Amelia is more concerned about the fact that Erica can't seem to grasp a glass. She wants to do some tests, but Erica puts the kibosh on that idea. Amelia convinces Charlotte to get hold of Erica's medical records. The news is not good. Mason's mom has an inoperable brain tumor.
Charlotte wants Erica to tell Cooper about her health issues. That's not going to happen. Furthermore, Erica promises to disappear with Mason if Charlotte says anything. Coop senses something's up with his wife, but he has no idea what's wrong. Later, Erica shows up to speak with Cooper in private. Charlotte stays behind with Mason. They practice more spelling. The word of the moment is "acceptable."
Sheldon has a session with Aaron, a cop who shot a young man. The kid had just been involved in an armed robbery. He reached for something, so Aaron shot him. As it turns out, the suspect was unarmed. Sheldon's police pal, Joe, wants him to rubber stamp this young officer as mentally healthy so he can get back to active duty. But is Aaron ready?