Board Thread:General Discussion/@comment-25202904-20141108163948/@comment-25399914-20141111195110

I don't know if they were or weren't married, it's just never mentioned in show so it was simply a possible reason for the names being different

I agree Pandoraz the relationships even if they weren't married meant a lot which is implied by the way Yang talks about both Summers death and her mum leaving Taiyang effected him.