I arranged to meet my mum today to go for a walk around Matlock bath and have an ice cream and some fish and chips in the gardens as it's my day off from work.This morning my sister also appeared at her house with my two year old niece before we left and it turns out she had rang her and arranged for us to take my niece with us as well. We've just got back and tbh it wasn't enjoyable it was a bit of a nightmare trailing a buggy and a child in this heat, she was hot and there were no toilets and she is only just potty trained. My mum has form for this and has done it before when we have arranged to go out together and we have ended up going round a farm park or other despite the fact that I have no children on my own yet. I love my niece to bits but aibu to want to be consulted first as it changes the whole dynamic of the day and sometimes I just want to spend time with my mum and have an adult day to be honest. I have tried to gently raise this with my mum before but she just accuses me of not liking children, which isn't the case as I spend plenty of time with my sister and niece. It's not for childcare either as my sister is at home today.