A great-grandchild is the child of your grandchild. If you have a daughter who grows up and has a son, that son is your grandchild. When that grandson grows up and has a daughter of his own, she becomes your great-grandchild.

The relationship works like a chain through generations. You are a parent to your children, a grandparent to your children's children, and a great-grandparent to your grandchildren's children. Some people are fortunate enough to meet their great-grandchildren, though this requires living a long life and having children relatively young in each generation.

The prefix great can stack up: a great-great-grandchild would be your great-grandchild's child, and so on. Each great adds another generation to the family tree. For a great-grandparent, holding a great-grandchild means seeing four generations of your family alive at once, which can feel like a remarkable achievement and blessing.