The context: I have 3 DC, one is living and working away from home, one is a student in another city and the youngest lives with us FT.
I receive child support from XH for the youngest, and when DD moved from school to uni he transferred her child support from me to her. She has plenty to live on with that, her loan and a term-time job.
DH has DC of his own whom he supports financially, and we each contribute to a joint pot for our household expenses. My ability to contribute diminished when DD left for uni with the halving of child support overnight but it wasn't a big problem as bills were lower too, especially food and hot water!
Now she's back for 4 months and I can't really afford to put my contributions back up to pre-uni levels to cover the extra costs. As it is unfair to expect DH to subsidise my DC as well as his own, would it be unreasonable to ask her for a contribution when she's found a summer job?