Police spokeswoman Kim Jones says officers responded to the W Hotel early Friday in midtown, though the reason for the fight was unclear.
Police say Tina Brown hit Shayne Brown in the head with a bottle. Police did not specify their relationships to the entertainer or to each other.
Tina Brown left the scene before police arrived. Shayne Brown had cuts on his head and drove himself to a hospital.
Bobby Brown has been seen this week in Atlanta, where his daughter, Bobbi Kristina Brown, is in a hospital. The 21-year-old was found face down in a bathtub at her home just north of Atlanta on Jan. 31.
People Magazine reported Thursday night that her family has been gathering at her bedside to say goodbye.
The daughter of the late Whitney Houston was rushed to a hospital this weekend after she was found unresponsive and face down in a bathtub at her Georgia home.
People reports the 21-year-old is on life support and doctors have said nothing more can be done for her.
PHOTOS: Bobbi Kristina Brown
Clive Davis says he's praying for Whitney Houston's daughter
Clive Davis says he's been in touch with Whitney Houston's family and is praying for her daughter, Bobbi Kristina Brown.
Davis, who was Houston's mentor, said in an interview Thursday that he's offered his support and prayers, "and they're so grateful."
"Of course it's heartbreaking to see the family go through this pain once again," Davis said at the Beverly Hilton Hotel, where Houston died in 2012 and where he will hold his pre-Grammy gala Saturday.
Police said the 21-year-old daughter of Houston and R&B singer Bobby Brown was taken to a hospital last week after she was found unresponsive in a bathtub in a suburban Atlanta town house. A statement from the Houston family this week said she was fighting for her life.
"They just ask that the public respect their privacy," Davis added.
Davis introduced Houston to the music industry more than two decades ago at his annual pre-Grammy soiree. He guided the big-voiced singer's illustrious career.
Houston was found unresponsive in a bathtub on Feb. 11, 2012, and died at age 48. Authorities found a dozen prescription drug bottles in her Beverly Hills Hotel suite and concluded that she accidentally drowned, although heart disease and cocaine use were listed as contributing factors.
The Associated Press contributed to this report.