DS1 (almost 5) is being a real handful at the moment, rude, not listening and telling lies about lots of silly things.
He spent the day at his Grandparents, they dropped him home. When he came in he started playing up, not listening etc. DS2 was screaming having a typical 2's tantrum, I was cooking risotto for the first time (turned out well considering).
My mum said 'DS1 said he didn't need suncream on as you put it on before you came', 'is that true DS1' i asked? he started laughing 'no, it was a lie'. So i told him off, he still laughed, I pointed out that he wouldn't find it so funny if he had got sunburnt because of his lie would he. Perhaps i was a little stronger than normal but he is pushing my button lately. Anyhow, mum and dad leave, mum seems put out. I called shortly after they left to make sure she knew i was not upset with her about no suncream (not actually been that sunny today) but was cross with DS1 for lying (again).
Got told off! She didn't like my attitude apparently and there was no need to tell DS1 off, etc etc.
So was unreasonable to tell him off for this? My mum makes excuses for him behaviour all the time. (good job i saved the telling off for being rude to my mum until after she went........she gave him £1 and he said 'oh i wanted £5! 
- she told me this he didn't do it in front of me)