My T doesn't have kids, but he has talked about other family members or himself to me with much the same goal, I think, as yours had. It felt fine. It has especially been helpful with my aging parents, as T has been through some of the same challenges with his parents. I work at a hospital with patients not too different in age from my own young adult kids, and once in a while I will say something to a patient about one of my children. It always has therapeutic purpose, and response has always seemed positive.

Recently, my daughter had knee surgery and the surgeon was going to have to make a decision during the surgery on which approach to take and what to do. This would occur without his being able to consult with us. He said he would choose a course of action based on what he would do with his own son. That did feel reassuring to us, and we felt like we were in good hands and like he was going to make the best possible decision while operating. So I think there are many ways a provider can "use" their own family in therapeutic ways with clients.