When my son was young and still at home and was seeing a therapist, we agreed that I could ask how it went and he was free to say anything or nothing.
Therapy is so personal and private. Even those closest to us are not priviledged to any of the details. Those people can support us in our therapy without knowing any of the details of what is talked about in therapy.
I talk to people online about some of my therapy, but most of it I keep between me and my therapist.