70% NTA, 30% NAH

(I'm not a parent, and probably will never be. Also take my opinion with a grain of salt, as I basically hate kids. Not in an "eradicate them off the planet" way, but more in an "please don't leave me alone with them" way.)

As long as you're not physically or mentally hurting them, kids need to learn to behave. They need to learn to take responsibility for their actions, and that they can't get out of situations by playing the victim.

Now, I guess 5 is still too young to understand this. But at 9 years, that's a whole different story.

On the other hand, kids are just kids. We probably behaved even worse at that age. Like, who is to blame? Actually no one. They probably just wanted to have fun. Maybe try a strike system? Like, for now you'll let them play Nintendo or whatever, but tell them if that happens one more time, then.. bla bla.