Kaka left Real Madrid to rejoin Milan just before last summer's transfer deadline, linking up with former Brazil teammate Robinho in the process.
The pair combined to create the opening goal in Tuesday's 1-1 draw with Barcelona, with the goalscorer Robinho adamant that he has shelved thoughts of signing for Santos in favour of a future with the Rossoneri.
He told Corriere dello Sport: "I'm well, I'm happy because my form has become ideal again and because I'm playing football and my brother Ricky [Kaka] has come back.
"We've always been friends, on and off the field. It represents a lot to have him back. I did everything possible to bring him back to Milan. My brother Ricky [Kaka] has come back.
"I admit there were long periods of doubt. I decided to stay with Milan, I renewed my contract for three years. I've put a lid on the return to Santos, at least until my contract with Milan is up [in June 2016]."
Robinho has found the target three times so far this season, helping ease the burden on Mario Balotelli at the San Siro.