Bit of a backstory:
I have 2 DDs, now 18 and 21. When they were 5 and 8, their dad passed away and we rescued 2 cats. They had 1 each. Sadly one passed away a good 5 years ago now and I let DD1 get another, so they both had a cat (due to their dad passing, it has brought a lot of comfort). DD2's cat got PTS this morning and she has asked if we could look at cats. DD1 was 15 or so when I got her a second cat, DD2 is 18 and although isn't going to uni, now works, etc. I have said that they are just too expensive (we did have insurance but still expensive) and I said that our financial situation is slightly different. I have told her that she can get one, but she has to cover the cost of it... She could afford to do this. She says that I should stop paying for her sister's cat and only pay half and then pay half for a new cat for her and so they both cover half. The thing is, I do think this would be unreasonable to DD2, as she was never aware of this agreement and wouldn't it be harsh to just put that on her now? I don't really know if I'm being U or not?