At my Brazilian Jiu Jitsu gym there are two fathers who bring their son(s) to class with them. I am really touched by the fact that they are able to share the great sport of Jiu Jitsu with their kids. Both of these fathers have great relationships with their sons, and the sons seem to really look up to them.
I am jealous of the fact that these kids got the opportunity to get involved in BJJ so early. It will help them learn to be disciplined and help them remain calm under pressure. These kids are well on their way to becoming a man and are leaps and bounds ahead of their pears who are wasting all their time on facebook. Instead they are learning how to defend themselves and getting exercise. In an age where one in three children are overweight or obese, it is important to make sure kids are involved in sports. If you can participate with them and set a good example for them at the same time, even better.
When I have children I will follow in these dads' example and take my kids to BJJ class and compete in tournaments.