How Jesse James’ Kids Are Coping

 Deano/Splash News Online

Despite Sandra Bullock moving out and their father checking into rehab, Jesse James' three children seem to be holding up just fine.

His kids, Chandler, 15, Jesse Jr., 12, and Sunny, 6, are staying at the family's Seal Beach, Calif., home "with a woman who looks like a grandmother-type," a source tells

The kids "are very comfortable with the woman," who has grayish hair and appears to be about 65-years old.

On Wednesday, the woman took Sunny to a local park after school.

"Sunny was having a great time on the swings," says the source. "She wanted to go higher and higher and, at one point, even stood up on the swing. She was laughing and screaming with joy while the woman pushed her."

Afterwards, Sunny sped through the park on her pink two-wheeler.

"She was riding fast and was very confident," says the source. "She had a smile on her face the entire time."

Adds the insider, "If she is aware of the crisis going on at home, you wouldn't know it by looking at her."

Meanwhile, Bullock, 45 – who stepped out briefly Wednesday to visit a Beverly Hills billionaire – remains in hiding.

Despite her plans to divorce James, 40, she still plans on staying in Sunny's life, according to the new Us Weekly (on newsstands now). With no biological or legal ties to the girl (whose biological mom is porn star Janine Lindemulder), "Sandra knows there are obstacles, but she doesn't care," a pal tells Us Weekly. "She will fight this with everything in her."

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