My DP is an excellent step parent to my children, I can’t fault him. They still see their dad (my ex) every weekend, but the relationship is tumultuous and there is a history of domestic abuse from him towards me. He still controls and gaslights me to this day, only I’m wiser to it now. He’s a real nasty piece of work and every time I have to have any sort of contact I find myself wishing he was out of the picture, but I know this won’t happen unless he goes to prison (again) or dies (unlikely but he is reckless and has been hit by a car recently and gets into numerous fights so I wouldn’t be overly surprised, not that I’d wish that on him despite everything). I’m not saying I want him to lose contact with his kids, but it does make me wonder… when a biological parent is out of the picture but hates the step parent (for no good reason other than jealousy) would it be acceptable for the step parent to take on the title of “dad” or take the step parent’s surname? That is what I would want so we would all have the same family name when my DP and I marry in the near future, but I feel that my ex (if alive) and his family would be forever bitter about it. What do other families do? I have known step parents to take on these titles and the kids to change names but only ever in the context that the biological parent had passed away when the family was still a happy unit, or the parent in question had never been present in the first place and wanted nothing to do with the child, but never a situation like this one. I know I have to put up with him until the kids are grown or decide they too have had enough (social services have their eye on him with regards to the children but haven’t put any measures in place at this point, but he’s not always great with them), but I had this burning hypothetical question that kept coming up in my mind and was curious to know if it’s ok to assume my DP could be known as dad and I could change their surnames if we ever ended up in that territory or if it’s a no go (children are currently under 5 if that makes a difference) thoughts appreciated, it’s not a major thing more of a curiosity because I doubt I’ll ever be in that position