They've got a friend in need ...

Jennifer Garner and Reese Witherspoon may be some of Hollywood's biggest names but that doesn't mean they can't take time out of their busy schedules to show some support for a sick friend at the Los Angeles Walk To Defeat ALS on Sunday morning.

The ladies, who were also joined on the walk by Courteney Cox and Renee Zellwegger, wore "Team Nanci" shirts in support of veteran publicist, Nanci Ryder, who was diagnosed with the disease over two years ago.

Jennifer brought her three kids for the walk and the family seemed to enjoy a day under the sun being of help to others.

One of our photogs said, "Jennifer was laughing and smiling the whole time. She didn't have a stitch of makeup on and looked beautiful. The kids looked like they having a blast on the walk."

Reese told People: “You just show up ... We have an incredible group of organized people, so when Renee calls me I just show up, or when Courteney calls me we just rally."

That's awesome that they showed up! Hopefully their star power helped such a needy cause!