That decision would be up to a judge but it needs to be brought before the court by someone who knows of the situation. The factors used to determine whether a parent is unfit are governed by state laws with child endangerment being the determining factor. A mother who is suicidal would likely lose custody of her child at least temporarily since her instability may result in harm to her child.
The following include some of the reasons a parent may be declared unfit:
Mother files motion for custody
Only can speak for Arizona: when the parents are unmarried, the dad has no rights except to pay child support. Of course if the child is old enough and the mom does not object, the dad can keep custody.
If the mom has custody. If they have to split custody then no she doesn't.
If mom has legal custody, call the police.
sole custody
yes
If you live in the US... Children are not property and therefore cannot be 'willed'. You can state in your will who you would like to receive custody, but the court is not required to abide by it. For example, if Mom has custody of a child, she dies and her will states that she wants her sister to receive custody, but Dad wants custody...Dad gets custody, unless he can be proved unfit, because Dad has first legal right to custody (Mom's wishes don't change that).
Then you will have to go back to court again to get it RIGHT.
Assuming you are an adult, yes you have a chance.
Unless specified in the court order, the husband or maternal grandparents. See Dads House Below
file for sole custody and file for child abuse and you will have possibly sole custody of thew child
Well, depends. Does Mom have custody? Is child under-aged?