Well, Ivar's title doesn't get passed on as he got it for being a younger son of a marquess. Same principle as Lady Diana/Sarah/Jane Spencer.Thanks for replying! That’s interesting. Okay, so he didn’t take his name but also doesn’t get any form of title? I wonder if that will remain the standard - seems a bit mean!
I also wonder what will be the case with heirs - in this case Ivar already had three kids. It will be super interesting to see what modernisation happens in this area now that it’s all legal.
There's apparently a group of peers' daughters who are pushing for change to absolute primogeniture since the monarchy was changed to that (pub quiz question - Princess Charlotte was the first British princess not to lose her place in the succession to a younger brother). While some, mostly Scottish titles, will go to a daughter if there is no son, most are of the Downton Abbey style where the daughters lose out.