Almost all of Tolkien's family trees are exclusively among what Treebeard calls the Free Peoples, and the Eldar call the Incarnates or
Mirröanwi: Elves, Dwarves, Men, and Ents.
Name three (or more!) parent-child relationships which do
not meet this description.
(For the purposes of this question, petty-dwarves, Hobbits, Druedain etc count as part of their ancestral races.)
hS