After his mother's death, Kehoe's father Philip married a much younger widow, Frances Wilder, and a daughter was born. On September 17, 1911, as his stepmother attempted to light the family's oil stove, it exploded and set her on fire. Kehoe threw a bucket of water on her, but the fire was oil-based and his action spread the flames more rapidly, which engulfed and immolated her body. The injuries were fatal and she died the next day. Some of Kehoe's later neighbors in Bath believed that he had caused the stove explosion.