Brolin – who accompanied wife Barbra Streisand as she performed at the Oscars Sunday night – said his son, 45, was watching the Academy Awards show at a party with famed film directors the Coen brothers and his daughter.
"He's great," Brolin said. "You know, everything is mutual. It's all okay."
Josh Brolin and Lane, 48, were introduced by Streisand at a 2002 party and were married in 2004 at the actor's California ranch. They were separated for some time before Lane signed divorce papers on Valentine's Day, a source tells PEOPLE.
"This was a hard decision for both of them to make," added the source. "The relationship just ran its course."
James Brolin said his son, who had been married before to Alice Adair and who has two children, was coping well. "Evidently he's doing well," said James of Josh. "Everything is fine."
Reporting by AILI NAHAS
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