A biological grandparent may institute an action or proceeding for visitation rights with a child adopted by a stepparent or a relative of the child where a substantial relationship exists between the grandparent and the child. Under no circumstances shall a biological grandparent of a child adopted by adoptive parents, neither of whom is related to the child and where parental rights of both biological parents have been terminated, be entitled to visitation rights. A court may award visitation rights if it determines that visitation is in the best interest of the child. An order awarding visitation rights shall contain findings of fact which support the determination by the judge of the best interest of the child. Procedure, venue, and jurisdiction shall be as in an action for custody. (1985, c. 575, s. 2.)