“My husband’s son lives with his mother in Tennessee and we reside in Minnesota. His son is graduating from highschool one year early – age 17 -. If he moves out of his mother’s home and goes to college, are we responsible to continue to pay her child support until his 18th birthday.”
Support geenrally continues until a child is both 18 AND graduated high school. If she is paying for his college expenses then the answer is going to probably be that your husband has to keep paying support until your son’s 18th birthday. If she is not paying his expenses at college, then your husband might try to get a modification so that the support goes directly to his son.