By Jen Heger - Radar Legal Editor
UPDATE: Both Ryan and Tatum O'Neal have arrived to the courthouse.
Ryan O'Neal plans on being at the LAX Airport Courthouse Thursday morning for his son Redmond's arraignment, RadarOnline.com is exclusively reporting.
It's a stunning development because Ryan has never gone to court for any of Redmond's previous appearances on his drug charges. Ryan wants to support Redmond, a source close to the actor tells us.
Redmond hasn't been formally charged by the Los Angeles District Attorney, but it's expected he will be facing a driving under the influence and a felony charge of possessing a controlled substance, heroin. Redmond will be arraigned in front of Judge Keith Schwartz, who handled Lindsay's grand theft case for a brief time.
Redmond is currently on probation for his prior conviction of a heroin possession charge.
He was arrested on Tuesday morning in Santa Monica after a police officer noticed Redmond's car run a red light. The officer was allowed to search Redmond's car because he's on felony probation and heroin was found.
Redmond's girlfriend was in the car with him at the time of his arrest. She was not taken into custody.
Keep checking RadarOnline.com for the latest developments in this story.
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