Lucas' grandmother is very hyperactive and believes that aliens will invade earth, revealing her slight insanity. She is however a caring grandmother who fights for her grandson's life when the ants take him. She is also very ditsy, which adds an unintentional humorous side to her.
Lucas' grandmother is a heavy, short woman. She usually dresses in sweats with aliens patterned on her clothes. She also has grey hair and wears dentures.