Photo credit: /WENN It's just a month after childbirth, but Reese Witherspoon already gets back in shape. The 36-year-old actress debuted her red carpet appearance since giving birth to son Tennessee James on September 27. She was all smiles when she posed for photographers in a blue dress by Rag and Bone while attending the opening of the label store in Los Angeles on Friday, October 26.

The "This Means War" actress was seen chatting with her friend Cameron Diaz and they were photographed together at the event. Other guests who attended the event were Emma Roberts and boyfriend Evan Peters, Brittany Snow, Aziz Ansari, Mandy Moore, Quinton Aaron, Carly Chaikin, Kate Mara and Shiva Rose.

According to US Weekly, Reese is rumored recording a duet with singer Michael Buble. Singing is not a new thing for the actress. She took a voice lesson when preparing for her role in the 2005 movie "Walk the Line". In the film, she played June Carter Cash, a wife of Johnny Cash. Joaquin Phoenix starred as the country music legend.