Of course you are related to the child of your parent's first cousin, second cousin or fifteenth cousin. You are related because at some point back in history the two of you have an ancestor in common. It may be your grandparent, or it may be a great great great... grand parent. But if you can show a common ancestor, you are related to each other. With higher numbers, the relationship becomes more and more tenuous.
Your parent's first cousin is your first cousin, once removed. A child of your parent's first cousin is your second cousin.
You and your uncle's child are first cousins to each other. You and your uncle's grandchild are first cousins, once removed, to each other.
Your child's children are your grandchildren. Your great uncle's children are your parent's first cousins and your first cousins, once removed. Your grandchildren and your great uncle's children are first cousins, three times removed.
Your uncle becomes your child's great uncle and your cousins are your child's First Cousins Once Removed. Did you know that President Barack Obama is a very distant cousin of President George W. Bush?
You and your first cousin's daughter are first cousins, once removed, to each other.
An uncle's nephew and the uncle's child are first cousins to each other. The uncle's great granddaughter and the nephew are first cousins twice removed to each other.
Your son and your aunt's child are first cousins, so your son and your aunts grandson (the son of your aunt's child) are first cousins, once removed.
Your uncle's granddaughter and your child are second cousins.
Your uncle's daughter is your first cousin. In the English language, it does not matter whether the uncle is a maternal uncle or a paternal uncle. All the children of your aunts and uncles are your first cousins.
Your great uncle's children are your parent's first cousins and your first cousins once removed.
It depends! For example, are you the uncle's child? That would make you and your wife first cousins. But you are not related to your wife's uncle if your only link to him is by marriage to her.
Your uncle's first cousins are also your parent's first cousins and so are your first cousins once removed. Similarly his second cousins are your second cousins once removed.
Your uncle's first cousin may be the child of your great uncle or great aunt. If so, he is also your parent's first cousin and your second cousin.Your uncle may also have cousins through his parent who is not a sibling of your parent. Those cousins, and their children, are not related to you.