Whatever is best for the child will be the soul purpose of the court's ruling. If the smoking parent is capable of providing for the child financially and emotionally better than the non-smoking parent - then yes, he or she will surely gain custody. If all else is the same in terms of providing for the child, then one can argue that the non-smoking parent can provide a healthier environment for the child.
There are many other variables to consider on top of smoking.
That factor alone probably wouldn't prompt a court to change custody; they will look at the whole home situations of BOTH parents.
Not without consent of the other parent. In Michigan the Parent with custody has to live with in 80 miles of the other parent, or get written consent from the other parent and get that consent approved by the courts to live outside of that 80 miles.
If without the permission of the parent or the courts.
Custody will only be affected if the step-parent is an unfit parent, abuses the child, or is a registered sex offender.
Prove to the court that you are a more fit parent. Or have her give them back if she is willing. Other than that you are not getting them back.
Joint legal custody, no, not if the other parent objects. You must secure their permission or failing that, the permission of the court which is the only authority that may override a parent's objections in such a situation.
It's a difficult question to answer without knowing the specifics. The simple answer is YES, if your kids are being raised by their other parent and you have financial means and they do not.
With an injunction
Unless you have the courts and the other parent's consent you will charged with kidnapping and the children will be brought back and you will lose custody and possibly your parental rights.
Not without permission from the court with agreement from the joint custodial parent.
Your kids and your lawyer need to have a little chat about that. NOW. The kids can feel guilty for being snitches.... better that than dead.
Yes. With joint custody either parent can change the kids school or any major desicion. The ideal relationship you would both agree on this but reality is always different.
Primary custody is generally defined as belonging to the parent with whom the child or children reside with the majority of the time. It does not mean that it cannot be a joint custody arrangement as well.