PRISCILLA TRIES TOUGH LOVE TO SAVE JUNKIE SON

Turns off his cash spigot

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MORE than a year after losing daughter Lisa Marie, Priscilla Presley has become so fed up with her junkie son, Navarone Garibaldi Garcia, she's turned to tough love and is refusing to give him any more dough until he quits drugs completely, sources say!

A family insider says the 37-year-old musician, whose dad is Priscilla's former lover Marco Garibaldi, has a habit of cleaning himself up, and then a month or two later falling off the wagon.

"It's been a vicious cycle that's lasted for decades now and Priscilla is desperately trying to help her son break it for good," says the spy.

As GLOBE has reported, Priscilla has seen too many members of her family die of drugs.