Naming baby the same name as husbands cousin

Karisa
I love my husbands cousins name and we were considering using it for our little girl. A little history....his cousin is 33 married (so has a different last name) and lives in California (we are in Texas). The family's are close but we have seen her 3 times in the 8 years we have been togeather. 
I told my mother in law we are considering that name and she said that it's a bad idea and they won't like us using it. She thinks we should ask them. Does anyone else think this is strange or is it just me?