FIRST PICTURES: Meet Reese Witherspoon's Baby Son Tennessee!

Reese Witheerspoon and her new son Tennessee James Toth sighting November 7, 2012 in Los Angeles, California. Credit: LB/FilmMagic

Witherspoon with her precious baby boy!

On Wednesday, Reese Witherspoon quietly debuted her infant son Tennessee James Toth, six weeks, while out and about in Los Angeles.

Wearing a light-blue denim shirt and jeans, the casual, slim actress, 37, pushed her bundle of joy in an Uppababy stroller. In another snapshot, Witherspoon picked up her little boy, named after his mom's home state; the adorable little blonde boy wore a green and blue sweater as he cooed on his famous mom's shoulder.

Born Sept. 27, Tennessee is the third child for the Oscar winner and her first with husband, CAA agent Jim Toth, whom she wed back in March 2011.

Witherspoon and ex-husband Ryan Phillippe amicably co-parent daughter Ava, 12, and Deacon, 8.

"The kids met the baby the first day at the hospital," a source told Us shortly after Tennesee's arrival. "Deacon is excited to have a brother. And Ava can't wait to babysit!" See more photos of Reese Witherspoon and Tennessee.

First-time dad Toth, meanwhile, has "been there for Reese every step of the way. [He's] very excited his son is finally here!"