You can command your children to do whatever you wish, as long as you aren't expecting other people to obey your commands also.
No, what I think is what I wrote.
If a person acts with courtesy online and shows respect to others, it reflects positively on him/her.
If a person acts rudely or crudely and chooses not to show respect to others, it reflects negatively on him/her.
What you choose to do is your choice—but actions have consequences, and one ought not complain about the consequence which naturally follows one’s behavior.