A lineal descendant is someone who comes from the same family lineage as someone else, like a grandparent, parent or great-grandparent. It means that you can draw a line from your family member to you and you are related because you share the same blood. If your mom or dad had a parent, that parent is also your grandparent and you are his or her lineal descendant. This means that you are part of the same family tree and you have inherited some of their traits and characteristics. It's like a big puzzle, and each person is a piece that fits in a certain place in the puzzle that has been passed down from generation to generation.