Conrad Hilton for sentencing in June 2015 Credit: David Buchan/Getty Images

Conrad Hilton has been ordered to spend at least 90 days in a clinic for substance abuse treatment after violating his probation last year.

The hotel heir was spared jail by his Los Angeles judge, despite calls from authorities to send him to prison for 60 days, the City News Service reports.

The authorities argued that Hilton had violated his probation by trespassing, failing drug tests, failing to complete three treatment programs and leaving California without getting permission from his probation officer.

The 21-year-old brother of Paris and Nicky Hilton was originally sentenced to probation and community service after his February arrest for threatening passengers and flight attendants during an international flight. Following his arrest and admission of having smoked pot in the plane bathroom and threatening to kill one flight attendant, he voluntarily checked into a rehab facility.

In June, Hilton's antics made headlines again when he was arrested for the second time in four months for reportedly violating a restraining order his ex-girlfriend Hunter Salomon had against him.

According to TMZ, Hilton was arrested after he broke into Hunter’s Hollywood Hills home. His ex-girlfriend — who also happens to be the daughter of Rick Salomon, the counterpart in Paris’ famous sex tape, 1 Night in Paris — filed for a restraining order after Conrad reportedly became obsessive and threatened to kill himself following their split.

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