Content warning: there's some offensive and transphobic language in this post
How do you stop him? There’s a variety of ways - handcuff him, cut his arms off, cut his legs off, remove every sharp object from the house, etc. But all of these things ignore the real question: Why do you want to stop him?
Transgender people need to be able to update their birth certificates with their chosen names and experienced gender because other people are so frequently jerks to transgender people solely on the basis of them being transgender.