Julia Roberts has been getting marriage guidance… from Susan Sarandon! That’s what sources say about the Pretty Woman star, 38, who apparently asked for advice when she and hubby Danny Moder, 32, ran into problems after their twins Hazel and Phinnaeus were born in 2004.

Said a friend: “It was the roughest period of their three-year marriage — with jealousy, time apart and fights about the kids. But they want to patch things up.”

Susan, 59, and her lover of 18 years, Tim Robbins, 47, aren’t married but have one of Hollywood’s strongest relationships.

They have two teen boys together and Susan has a 20-year-old daughter from an earlier marriage.

The friend said: “She told Julia and Danny to think about why they had kids in the first place — their love for each other.” The two families met up for a Christmas Eve dinner — and Susan’s tips seemed to be working.

Said the friend: “Julia had the happiest house in the world this Christmas — and she owes a lot of it to Susan’s wise advice.”