German Law on Kids right to make noise (Nuremberg)

Hi,

I have a 5 years old son who is very playful and like to remain involved in an activity all the time. I live in a family house with 4 apartments but problem is that 2 tenants dont have a kid and one has a 12 yr old. As a result, these neighbors are all the time complaining about noise from son to my landlord. This is ongoing for nearly two years (when my son was not even 3). Continuous efforts on my part to keep him quite are turning into a psychic problem for me. Can any one advice what should I do as I really want to take some sort of action IF laws are on my son's side.

Regards

Kashif