Would I be messed up to threaten legal action?

My son passed away 8 months. He passed to suicide at his dad's house. There is a person making public videos and tiktok about how my son did not commit suicide and that his dad murdered him. All of her "evidence" can clearly be debunked and it's causing us a lot of pain. Especially my ex. I'm not the type to threaten legal action all the time but I've already messaged this girl and she left me on read.