COSTAR CRUSHES VAL’S PRISTINE IMAGE!

Mackenzie Phillips spills on alleged teenage coke parties

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CUTIE pie Valerie Bertinelli has enjoyed a goody-goody image going back to the sitcom One Day at a Time, but her sister on the show — admitted bad girl Mackenzie Phillips — drops the bombshell that they were secretly sharing cocaine way back then.

The 66-year-old Mackenzie — daughter of the late Mamas & the Papas singer John Phillips — says she and Valerie would enjoy lunch breaks of wine and cocaine when they played sisters Julie and Barbara Cooper on the hit series from 1975 to 1984.