I will try to keep this short and to the point. I am a regular poster/lurker but namechanged as Dsis might recognise.
My Dsis was up for a few days and bil arrived last night. I dont particularly like him as he is very over dominant towards my sister but thats a whole other story and I am always polite and friendly for the short period I see him (1 day 1-2 times a year)
My mum was bring a very elderly relative to visit today so before they arrived I asked Dsis when they went out to the shops to ask bil to leave a free space outside my front door, and park after my neighbours car (2 spaces down) My relative is 90 and frail and its very icy outside so I wanted mum to be able to park at front gate as she always does.
They came back from shop and still parked in space in front of house. I was a bit
and when Dsis came into kitchen I said can you not move car, she seemed aggiatated (I think she had asked bil in car and for whatever reason he refused, probably because shes asked him to do something) So dsis shouted to him can you please move the car and bolted upstairs to bathroom. Bil then approached me in front of DC very confrontational and said 'No i'm not moving the car I dont see why I should' I explained my reason why and he said 'no, I think there is enough room' I said there wasn't as relative would now have to walk down icy road then squeeze past the car. He kept saying no and I was getting really aggitated at him as I was very
as to why there was an issue at all.
Dsis came downstairs I explained what was going on and she took his side and they left in a huff 
I am now sitting very baffled and going over it all in my head. Surely I didn't do anything wrong!! If I was visiting and the person asked me to move my car I wouldn't hesitate or need a reason I would just move it.
So AIBU I can't see it from his side at all!!!