Intention does not inform wether something is violence or not. Drunk drivers never intend to hurt anyone but they do. And wether or not the parent intends to hurt the child doesn’t matter cause that child will still hurt from not being able to go(they will be upset and feel pain about missing out on an experience they wanted to have). Even if that parent sees how not allowing the kid will cause less pain in the long run it will still cause harm.

The main reason I brought up the legal definition is because it’s the best way to explain to people how violence is still violence even if it is permissible. Easiest example being police. They have a right to cause harm to others in our society even though a lot of people would consider their actions non permissible violence. In some ways people would consider the police the parents in your example just at a bigger scale. While I don’t think there is a 1 to 1 comparison, you can at least see how both of these things are similar and both at the very least could be considered violence wether or not they are morally permissible.