Mona is Bart and Lisa's...
Grandmother/Grandma
Homer and Marge are Bart's...
Parents
Marge is Homer's...
Wife
Homer is Marge's...
Husband
Selma is Lisa's...
Aunt
Herb is Bart's...
Uncle
Bart is Herb's...
Nephew
Bart, Lisa and Maggie are Ling's
Cousins
Ling is Patty's...
Niece
Maggie is Homer's...
Daughter
Abe and Mona are Lisa's...
Grandparents
Bart is Homer's...
Son
Abe is Bart's...
Grandfather/Grandpa
