I've seen Isabelle Elizabeth (or the reverse) in a few BAs, which has made the name nerd in me cringe. Same with Lillian Elizabeth (though that etymology is admittedly less obvious - a lot of people probably connect Lillian to Lily rather than Elizabeth).
Went to college with someone who had two sisters named Caitlin and Catherine, and while I never said anything that definitely irked me, because I feel like that's a really obvious way of naming both your daughters the same thing. (This wasn't even a cutesy twin situation, either.)
***
Please rate my personal name lists:
www.behindthename.com/pnl/69381www.behindthename.com/pnl/69381/117507www.behindthename.com/pnl/69381/109399www.behindthename.com/pnl/69381/132018