My fiance and I are happy to have children at our wedding and have a number of them invited. However, one of my cousins has 3 children and has lived out of town since she got married. While I know her well & we grew up together, I hardly know her children and I don't think they would recognise me/know my name. As such, we're inclined to invite my cousin and her husband, but not their children. The rest of the children in attendance would all be my first cousins, and in my fiance's case second cousins as he has a small family compared to mine - all children we see regularly/are close to. How can we make it clear on our invites that my cousin is invited, but not her children, without coming across as impolite?