This is probably best explained with an example.
Alice and Bob have a child, Erin. Bob and Carol have a child, Frank. Carol and Dan have a child, Grace. Clearly, Erin and Frank are half-siblings, because of their father, Bob. Similarly, Grace and Frank share their mother, Carol.
Erin and Grace have no parents in common, and are thus not half-siblings. However, is there a term for their relation?
Best Answer
I just read of a term called cross siblings. Where you are not legally or biologically related but you share a half sibling. My kids are tech half siblings but we never call them that because they are growing up together with me. But they both have half siblings, and the half siblings have half siblings. And it can make your brain hurt trying to explain it all lol. But because of this I've googled it a few times. And came across a girl in the UK who uses the term cross sister when it comes to the girl she shares half brothers with, I then googled it and have found it has multiple hits. I don't know how legit the term is but sure is easier to say than brothers half sister or half brothers half sister.lol