Absolutely not. I find the concept horrifying and patronizing. I'm not a little kid and I'm not their kid either. I also often get people in shops (cashier) or at the hairdresser to adress me with "tu" instead of "vous" (in French) because somehow they assume that I'm 14 years old (?) which is baffling to me since I'm 30. I hate it. It's the same with a therapist.