Unfortunately in Minnesota there is no set age at which a child can decide who to live with. (I have heard that this is true in other states, and for some reason a lot of people do believe it to be true). When a court is looking at deciding custody matters, the court considers "the best interests of the child," 13 different factors which include the relationship between the child, parents, and others in the home, adjustment to home, school and community, mental and physical health.
One of those 13 factors is "the reasonable preference of the child, if the court deems the child to be of sufficient age to express preference." How much weight a court gives this factor really depends on the situation. Whether a child is deemed to be of sufficient age also depends on the situation. A 12 year old who expresses a desire to live with Dad because Dad picks the kid up from school, coaches soccer, helps with homework, and enforces bedtime is going to be taken more seriously than a 17 year old who wants to live with Dad because Dad is never home and has a fridge full of beer.
Your best bet may be to sit down and have a conversation with your mom. Let her know you love her, but you have been wondering what it would be like to live with your dad. Maybe together with your parents you can work out an extended visit with your dad.
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