You will Watch The Grim Adventures Of Billy and Mandy Season 1 Episode 4 online for free episodes with HQ / high quality. Stream cartoons The Grim Adventures Of Billy and Mandy 104 Grim vs. Mom: After having a nervous breakdown and leaving the house in the first episode, Billy’s mother, Gladys, returns. She meets Grim again and, this time, she plans to destroy him once and for all. When Grim goes to the kitchen for a glass of water, Gladys attacks him and shatters his skeleton. In the end, Grim assures the kids that Gladys has won the battle but not the war.