Legwork: Looked up 'identical cousins' (useless), 'genetic multiplicity' (not even close), family resemblance (dead end), 'genetic likeness' (relevant, but ultimately unhelpful), and even spoke with a medical school friend (just as stumped as I am). Checked tags here.
Basically, I've got a set of 'identical' cousins. No, not genetically identical, or even physically, really. But close enough that if you only know one of them, and you see the other unexpectedly, you may find yourself a bit confused at first glance.
I've heard a term for this, but I cannot remember what it was for the life of me. And not knowing what it's called is making it very difficult to properly research it.
* What is the term for this phenomenon?
* How common/likely is it to happen?
* Are there certain relations within a family where it is more likely to happen?
* Would the parents (both mothers or both fathers; not a case of identical twin females marry identical twin males) of the cousins being identical twins increase the odds of something like this