Discipline... table manners... behaviour!!

[Picklebob123]

3 kids, 3, 5 and 6(nearly 7). The 6 year old is terrible at the kitchen table.

Dosnt hold both his knife and fork.
Leans on the table
Eats mouth open.
Constant talking and not eating.
Messing around (rude words.. poo, Trump etc).
Takes forever to drink after meals.

Any advice or discipline options, I've shouted, I've asked nicely, I've nagged, meal time are so stressful.

Does he behave like this at school? It is quite young to have full blown table manners - that's my view though.

I'd ignore the behaviours, but engage in conversation with him. If he's not finished eating by the time the others are, let them get down from the table but you stay with the 6 year old until he is finished. He may well soon see that if he eats properly then he can get down at the same time as the younger two.