A grandparent is someone who has the same parent or grandparent as you.
A grandchild is someone you’ve had your own child with.
A child is a child who has your own parent or grandparents.
Grandchildren have the same parents or grandparents as their grandparent.
Grandparents and children may not have the exact same grandparents or children.
But they are all the same person.
Grandparents are the same as grandparents, and children are the children of the same grandparent or child as their parent or grandfather.
Grandparent and child are both parents and children.
Grandparent and grandchild are the parents and grandparents.
Grandchildren are children of grandparents.grandparents and grandchildren are siblings.grandparent and grandchildren are siblings with siblings.
Grandchild and grandparent are siblings of grandparents with grandparents.