@matigo Threats, hitting, or vandalism gets them a time out. One minute for the two year old, two minutes for the five year old.
For time out, everyone just leaves and closes themselves away from the timed-out kid and ignores them. After timer is up, when they’ve been calm for say 10 seconds, come out and move on with things. Not a time to talk it over. Remind why they were in time out, and on to the next thing.
They do not like time out. It is not a frequent need. More effective is praising good behavior whenever performed. Recommend The Kazdin Method for further reading.