File suit for value of dog. Be prepared to prove how much dog is worth.You should prove that the property is yours and that you have a right of its immediate possession to win a replevin action. You will then file it and serve it on your ex. Additionally, If an Ex has taken possession of your pet, we may be able to help you with a "replevin" action, which is a legal means of recovering property. People who believe that their animal is being wrongfully withheld can commence a civil lawsuit (replevin action) to try to get the animal returned. Section 433.117 - Legality of distress determined in replevin action. In other words, in a replevin action the remedy sought is the return of detained property plus incidental damages. The process of starting a replevin action usually begins with filing a complaint. You need to file a replevin action with the Court of Common Pleas of your county.