Six year olds are kids, right? In fact, they haven't really started to develop at all. If there bodies are changing, that's too young and you want to talk to a doctor. Between six and eighteen, a lot is going to happen to the body, so you want to start talking to a six year old about the slow process of body change. The most important three things you need to talk about with your child are; nutrition, exercise, and sleep. You want your child to eat for health. That means your child needs to why they are eating what they are eating. If you just say, "Eat your vegetables." It is not going to resonate with them, but if you say, "Hey, this broccoli has a lot of calcium. This calcium is going to make your bones strong." Help teach your children why they should eat the healthy foods you give them and why to stay away from the junky or sugary foods. The second is exercise. Your kids need exercise at least 60 minutes a day. It's important for bone and muscle health and it's important for prevention of diseases later in life. Really talk to them about their exercise and make sure they are having fun when they exercise. The last thing is sleep. If your kids know that they grow when they sleep, they will put themselves to bed. I guarantee you. Talk to your six year old about sleep. They need 10-12 hours a night. Some kids need more, some kids need less, but make sure to emphasize for your kids that they will grow well when they sleep. I promise, they will say, "I'm ready for bed." They will get into bed and turn off the lights.