Long story short - a long time friend of my eldest daughter is changing her surname by deedpoll. It's for professional reasons - I thought it a bit odd as her original name is 100% fine. Her family are completely okay with this. She is early 20's. My husband as taken huge umbrage at this - how awful it is, how if our eldest daughter did this he would expect me to "back him up". This was a month or so ago. Tonight for absolutely no reason out if the blue he starts going on about it again. Asking if he thinks our daughter will do this ( I can think of no reason this even a minute possibility - it is in his head). Again how he would expect me to back him up (not sure what this would mean - being angry? Disowning her?). I said I would find it very strange but ultimately as an adult it really wouldn't be my business. He has got in such a huff about this imaginary situation he is sleeping downstairs!! They haven't always had the easiest relationship but this is ridiculous! He can be a bit controlling at times and over the last few years a real sexist attitude as been shown ( he did not have it when he was younger but is turning into his dad). I find his behaviour about this really weird - not sure what to do or say to him.....