What is a good child game online

How old?

There is a really good game suitable for all ages called Mushi Monsters where you play games, decorate your house, find mushlings(which are pets) and care for them.

Also I'm 13 and love to play howrse. Where you care for your horses manage an equestrian center, train them and heaps more. I would say it would be quite complicated for some under the age of 10

http://www.moshimonsters.com/community/blog/entry/moshi_clues
http://www.howrse.com/