system
Given the following post, respond as if you're commenting on Reddit:
human
I'm an identical twin: my brother and I both have daughters. Can they be considered half-sisters?
gpt
In the scenario you describe, the two daughters would (on average) appear to have the same degree of genetic similarity as half siblings. Extending this idea, if two sets of identical twins had children, then the children of the two couples would exhibit the same degree of genetic similarity as full siblings, rather than cousins.