Cat Siblings
A deleted Reddit user considered his two cats to be extended members of his family, but as it turns out, his cats already had a genetic family member in their lives and they were under the same roof.
“Had two cats. Adopted them at different times, and they were the same age or close to.
They both got sick and had to be taken to the vet. He took blood tests on both of them, said he noticed similarities and then ran them against each other. I don’t understand what exactly he did but it revealed that they were related. Yep, brother and sister. They were adopted years a part, one as a kitten and one at 2 years old. Barely lookalike either. Honestly couldn’t believe it.”