Pat Harrington Jr. as building superintendent Dwayne Schneider. Credit: CBS via Getty Images

Pat Harrington Jr., the actor best known for his portrayal of Dwayne Schneider on One Day at a Time, died on Wednesday, January 6. He was 86.

Harrington's daughter Tresa confirmed the news via Facebook on Thursday, and said her father was surrounded by his family members when he passed away. Tresa's update was shared two months after she disclosed that Pat was suffering from Alzheimer's disease. His cause of death remains unknown.

"I know many of you have lost parents and loved ones, and now I know what it's like to feel the kind of sadness and void that will never be filled but only softened with the passing of time," his daughter wrote on Facebook. "My heart is broken to pieces and I will cry and cry until I just won't."

Harrington will be best remembered for his inimitable turn as handyman Schneider on the sitcom — opposite Bonnie Franklin, Valerie Bertinelli and Mackenzie Phillips — for nearly a decade, from 1975 to 1984. He won an Emmy for the role in 1984 and a Golden Globe in 1981.

His last television stint was on his longtime former costar Bertinelli's recent TV Land sitcom, Hot in Cleveland. He also made appearances on Curb Your Enthusiasm and The King of Queens. He is survived by four children.

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