I didn't quite finish my thought - he's a little boy who cannot control the important thing - mum and dad getting on and living together. Or his TV watching. On school you don't get any control.
And sounds like his mum is fairly controlling.
So this slight stroppiness may be the only place he can have a bit of control - and the more he sees you upset, the more he wield power. Good luck.
Alphabetical Girls' and Boys' Names Oct '25



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But lovely as they are, they are often stroppy little so and sos that take it out on good old Nana who will never get more than a tad tetchy!