Vehicle itself covered by the ADAC or only the driver?

Moin, moin. Now that I have a car again after a long time, I wanted to apply for the ADAC membership. However, my brother said that I did not have to because it looks like this: My brother is a member of ADAC. I run my car with my brother as the second car with the insurance. So he is also registered on the vehicle license as owner. My brother said that everything goes on Him, because he is registered as owner of the vehicle and he is a member of ADAC. Is that true?!