Legal Question in Personal Injury in Missouri

If you are the biological mother, and the adoption has taken place, you may have few if any actions to take through the courts. You can't sue for ruination of a relationship with a child that the state already ended.

If you are the child's father, ( and your rights were not terminated in the adoption) there may be several avenues open to you. Presumably you and the adoptive mother are not living together, and there is a custody/visitation plan in place. Those have an at least implicit obligation not to harm the child's relationship with the other parent. You may be able to seek a finding of contempt in the same court that decided the divorce and custody issues. If there is no Custody Order from a Court, then you will have to resort to filing a tort claim in civil court. These are not often done, but still available under the right set of facts. You will want to consult directly with a family law or civil practice attorney in your area. You weren't able to provide enough facts here to evaluate your situation.

Good luck

Can you prove it is slander? Who is your witness?