 He also has a baby sister named Kate and a pet dog named Pal.Appearances from Arthur's extended family include Grandma Thora (David's mother), Grandpa Dave (Jane's father), Uncle Fred (Jane's brother), Uncle Richard, Uncle Bud, Uncle Sean, Aunt Jessica, Aunt Loretta, Aunt Lucy, and his cousins Cora, Monique, Ricky, George, and other unnamed relatives.However, the only two members of Arthur's extended family who have appeared more than once are Grandma Thora and Grandpa Dave.