Winter, 14, is one of the stars of the ABC sitcom "Modern Family."
She was placed under her older sister Shanelle Gray's temporary guardianship after she made allegations of physical and emotional abuse against her mother, Chrisoula Workman.
Workman was ordered to stay 100 yards away from her younger daughter for the time being, as well. The family is due back in court Nov. 20.
Gray was also removed from her mother's care two decades ago and never went home.
But Winter's brother, Jimmy Workman, told UsMagazine.com all the abuse claims are untrue.
"There is no truth to these allegations," he said Wednesday. "The allegations made 20 years ago are not true and the ones today are not true. ... This is a mother who does everything for her kids. ... Chris misses Ariel and wants her to come home."
"It's all untrue. It's all untrue," Chris Workman told People.com Wednesday.
Court papers filed Oct. 3 in Los Angeles accused Workman of "ongoing physical abuse [slapping, hitting, pushing] and emotional abuse [vile name-calling, personal insults about minor and minor's weight, attempts to 'sexualize' minor, deprivation of food, etc.] for an extended period of time."
"I have my doctor's letter that my daughter's never been abused," Workman told People.com. "I have stylists' letters that she's never been abused."