How to deal with b*tchy in laws.

Ok so I’ve never really liked my husband’s brother or sister, but lately his sister has been more insufferable than usual. She cannot take a joke at all. My husband posted a joke on Facebook and she took personal offense to it and yelled at my husband, and called me out for some weird reason? Then my daughter jokingly commented on her page teasing her and her daughter, and she got mad at that too. When I explained our daughter was just teasing, she rolled her eyes at me. Has anyone else dealt with stuff like this where someone just takes offense to everything?