You will be missed, Pat Harrington Jr.

The iconic actor — who portrayed the cocky superintendent Dwayne Schneider on the hit sitcom One Day at a Time — has sadly died at age 86.

His daughters Tresa and Terry took to Facebook to announce the sad news, revealing that their famous dad died from Alzheimer’s on Wednesday, Jan. 6 surrounded by friends and family in LA.

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pat harrington jr.

Pat on One Day at a Time in 1975.

Pat had a long and successful career. Though he was most-known for his role on One Day at a Time from 1975-1984 — which won him a Golden Globe in 1981 and an Emmy Award in 1984 — he also made appearances in a plethora of shows including The Love Boat, Make Room for Daddy, The Munsters and most recently Hot in Cleveland.

Our thoughts are with Pat's family during this difficult time.