Ann comes across as rather entitled but I can relate to her, to some degree. I come from a farming family and have married into a farming family.
There is usually some degree of resentment over how things will go because in order to keep a farming business moving through the generations it can't be split up, so one sibling/cousin always does well at the detriment of others.
I'm very sentimental and I like to keep things safe. We moved into my DHs grandfathers house which is not at all dissimilar to WFH. I felt sad for DH that prior to us moving in, there was some mad scrabble for anything of value and we moved into something which had been effectively ransacked. My brother is my polar opposite in that he will sell his granny for a quick quid. We get on very well but I could see in a situation like that me wanting to safekeep family items so that he couldn't sell them to the highest bidder without us discussing their value to us as a family.
If Jeremy is depicted accurately in this episode, it's a very odd way to conduct yourself when you're trying to get away with murder. The partying and having friends to roam around his parents house seems so far fetched.