You're right, with a lot of cousins, some overlap or similarity is bound to occur.
My SIL had her daughter in 2005 and used a family name that we had been planning to use. I was sad, but since I wasn't pregnant, I had no real claim to the name. During her hospital stay, we talked about other baby girl names. I told her my *new* favorite (since she had just used my *old* favorite). Guess what baby girl #2 was named? My *new* favorite.
We were both pregnant with boys at the same time, she was due 6 weeks before me. We had our name picked out since I had been about 8 weeks pregnant. She had no name picked out. My husband mentioned our name to her husband. Guess what baby #3 was named? My EXACT name. Three times in a row.
The first time, not her fault, it's a family name and I wouldn't have cared. The second time, she *could* have forgotten where she heard the name, so I give her the benefit of the doubt. The third time, it's possible that hubby came home with a great idea for a name, but didn't tell her where it came from.
Just in case, all baby names are secrets from now on. :)