I'm in KCMO. and the answer is no. See related link.
no, but depending on time, support can be adjusted or stopped. In Missouri, after 30 days, it stops.
No, it's up to the court. However, the non custodial parent would traditionally become the custodial parent. The parent should always have first right to their child!
That is an issue the court decides at the time other child support issues are addressed.
16yo can not choose custodial parent at all. The court might listen to your opinion but that is it. And no, step parents do not have any legal right to the child.
No. The court will decide.
When they are 18,
Depends on how often the custodial parent is violating the court orders.
A child can not do this so you have to be 18.
Once you are 14 years of age you can choose if you want to live with your mother or your father. you have to talk to a judge about it so they can make it legal for you to move in with your other parent and make it so they have costody over you. ~Erica~ Minors are not allowed to choose with whom they wish to live, this includes parents, grandparents and other relatives. In cases of parental custodianship the court usually does not intervene when a minor moves from the custodial parent's home to the non custodial parent's home until (unless) the custodial parent files a request to have the minor returned to the primary residence. The matter can become very involved especially if there is a child support order in place pertaining to the non custodial parent. If this is the case said parent cannot cease paying child support without the risk of being in contempt of a court order and thereby incurring futher legal difficulties.
No, see link
see related link
A minor can not choose where to live. That is up to the parents or the court depending on the details. If your non-custodial parent who lives out of state wants you to live with him/her, they have to petition for custody unless your custodial parent will consent to the change and join in a modification of the custody order.