Everyone at the powerplant thinks Homer is crazy when he shows up in a pink shirt and want to give him a mental health exam. He has Bart take it for him and ends up in a looney bin with Michael Jackson.
Grampa falls for an old woman, Beatrice Simmons and when he goes to celebrate her birthday, Homer drags him away. Bea ends up dying that night, and Grampa blames Homer for costing him their final moments together.
Homer: (Wearing glasses) The sum of the square roots of any two sides of an isosceles triangle is equal to the square root of the remaining side! Man: (From inside a bathroom stall.) That's a right triangle, you idiot! Homer: D'oh!