My sister ( married - 1 kid in private school - she and husband don't really work - live off some investments n live frugally) invited my mum down ( 6 hour trip) for the weekend to watch my niece ( her only granddaughter) at a school event.
My mum - 70's reasonably well off but my dad's in a nursing home n she is selling things off and downsizing as a result.
Me - partner but no kids sadly, both work full time in reasonably well paid jobs. We're not high life but do spend on clothes, holidays, meals out with friends etc.
Both my Mum n I give niece/ granddaughter nice birthday n Xmas gifts. Sister tends to ask for a specific and substantial item ( fine).
At event, sis pipes us she has taken a tenner off my mum for 'our' 2 tickets n that I owe my mum a fiver. I am shocked but try to repay my mum who refuses. I pay for some drinks to contribute.
Next morning I tell my sister it is wrong, ridiculous n mean spirited to invite us n most particularly our mum to event n not cover cost of the tickets when they are so cheap (n point out cost of my dad's nursing home fees). She doesn't apologise or repay mum.
BTW It is my sisters birthday next week n my mum will be giving her a generous cheque (she always does).
My mum knows my view n that i I spoke to my sister re tickets. Do I speak to sister further or leave her be as a lost cause.