Though, Tony is only four years old, he can use the mouse to navigate the software. He knows the key sequences to get to where he wants to go. He can't read but he learned them by watching father show him once. He was able to watch all the six types of trains on MTS without assistance from his father.
Getting him off MTS and telling him to go to bed isn't easy. But Father knows Tony will wail for five minutes before there is something else to play with.