Do children wear mrc or cry in the traditional sense?

My child is nine years old. I watched this MRC for two years before, and I don't believe it. Later, the student's plot passed for a year, and then I went to the dentist this year and chose this MRC. You just need to wear it to sleep every day. Children often fall asleep and throw up in the middle, but the next month they really see the effect. Now it's the fourth month, my teeth have been put in a little, and my mouth is not so prominent. Last Sunday, I changed the second set of braces, which seems to be three sets of braces together a year. We charge by the year, almost 5 thousand a year. If it is not corrected within one year, it will take more time. I feel that one year at home should be enough.