Redmond O’Neal was arrested again on drug-related charges while on a 24-hour pass from drug rehab, RadarOnline.com has learned exclusively.

The son of Farrah Fawcett and Ryan O’Neal was taken into custody on Dec. 29.

He is in court Tuesday for a status update on his rehab. Now he’s facing up to six years in prison because his latest arrest violates probation terms of a previous drug offense.

EXCLUSIVE: Ryan O’Neal Visits Redmond Weekly In Rehab

Redmond had been clean for six months after battling drug problems for years.

When Redmond returned to Impact, a drug and alcohol treatment center, after his 24-hour pass, the staff noticed he seemed altered.

This was his first 24-hour family pass out of the facility.

EXCLUSIVE: Judge Issues Redmond O’Neal Stern Warning

Redmond was ordered into rehab by a judge because of his many previous offenses.

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