Grandfather: The father of either the boy or girl's father or mother.
Grandmother: The mother of either the boy or girl's father or mother.
Father: The male parent of either the boy or girl.
Mother: The female parent of either the boy or girl.
Boy: The male child of the father and mother.
Girl: The female child of the father and mother.
You can identify each family member by their gender and their position in the family tree. For example, the person sitting at the top of the tree is likely to be the grandfather or grandmother, while the parents would be sitting in the middle, and the children at the bottom.