What causes trigger thumb?

Anyone’s little ones here have trigger thumb? How old were they when diagnosed and did it go away on its own? If so when? And if not, what kind of treatment was needed?

My cousins son had it. They diagnosed him at 2 years old. Depending on the severity of it, physical therapy can treat it or a minor surgery. Her son needed the surgery

My son did. I noticed it when he was about 3… but I didnt know what it was. His doctor blew it off. By the time he was 7 it caused him so much pain so I went to a different doctor and he ended up having minor surgery. It was super quick and easy! He is now 9 and has zero issues with it.

My best friends son had it in both thumbs and they had to do surgery.