My child is on the verge of believe /not believe or my child doesn't believe...

Yep. Seems like this happens to everyone eventually. First off, I am in fact a real person, therefor Santa is a real person. Lots of real people, actually, but that's not what the belief is all about, really. Belief in Santa is a belief in the magic of Santa. It's more than a fat guy with white hair and a white beard in a big red suit. If you're child is a non-believer or is on the verge, have them watch the film "Dear Santa," which is a documentary on the USPS Operation Santa program. Or take them to volunteer at a local homeless shelter or soup kitchen. One of my favorite things to do when this comes up is to give them a task designed to teach them the magic of Santa. I'll suggest that they find someone with a need that they are able to fulfill. Could be a classmate who needs a new coat, or a neighbor who needs their yard taken care of or a homeless person who needs a meal. It doesn't have to be expensive or time consuming, it just has to be an actual need  that the kid is able to fulfill. Then I tell them to make sure that they provide that need and do their best to never let the recipient know where it came from. I go into a bit more detail on this concept in a recent blog post about two teenagers. You can read that post here.