With one of them I honestly don't remember. It feels like we just met one day.
But with another one I remember very clearly. I went over to his house when I was in 1st grade because his mom was babysitting me after school that day. We opened the door and he was on a flattened cardboard box at the top of the stairs. He was planning to slide down and out the door, but the problem was the stairs weren't directly in front of the door so he ended up hitting the wall because he found out that you can't steer cardboard.