Mum’s “neglect” of chickens?

I’m not too sure where to start, but a few years ago my mum started getting ex-battery hens go out in the garden. She grew up with chickens when she was younger so they are not a new and mind-boggling pet to her. I believe the main attraction for her was you can get them from the farmers market for like a couple of quid each (she is so cheap) and they do lay nice eggs. They are in a coop outside that my dad‘s made.

This isn’t something that affects my daily life as I haven’t lived there for 10 years because as well as neglecting animals she also has neglected her children LOL. However, with Christmas coming up it is inevitable I will probably have to go back for a couple of days. Every time I go there depresses me. She doesn’t put any wood chips or straw down in the coop so it’s full of claddy mud, so the once lovely chickens stand in their own filth and the group is liquidy and sloppy. We live in England so it is a soggy sad country And I just feel so bad for these things. Their life is possibly marginally better than before but it’s just not good enough. There are so many ways to prevent them living in this slop but because of her narcissistic tendencies, anything I say does not get through. Other pets we had previously have died due to neglect (which breaks my heart) and she refuses to take any of them to the vet. For example one of the chickens has a big tumour on it. The once gorgeous chickies are obviously stressed too, because they peck each other else to shit. I used to enjoy cuddling them when I would come back in previous years, they were sweet animals but it’s got to the point when they are too gross.

So basically, I do not know what to do about the situation as it weighs possibly more heavily on me than it should. I was thinking when I go back I just dumping a load of wood chips in which I always do every time and I make sure they are fed with some nice cut grass but nothing I ever do is enough because I go back there so rarely. It is a similar tale with two amazing long-haired guinea pigs they have. They are such sweet animals but also not looked after well enough. For some reason, it falls on me when I go back every few months to cut their nails and cut their hair; the run is always full of poos and stinks. It makes me so upset. I am thinking of it all more now because of Christmas approaching.

I don’t really know what to expect by posting this maybe I just need to get off my chest. I love animals and any person would be upset to see them treated this way when they deserve better. What would you do?