United Kingdom, Oct. 10 -- Jessica Biel's 11-year-old son couldn't hide his disapproval when he saw the barely-there green dress she wears in her new movie.

The 44-year-old actress takes on an action-packed role in Matchbox: The Movie, and also has the opportunity to show off her incredible figure in one particular scene.

However, Jessica's son Silas - who she shares with husband Justin Timberlake - was less than impressed when he saw the plunging gown.

She told People: "My son, Silas, was very concerned about the green dress [I wore in the movie]. He was like, 'What are you wearing, Mom? Yuck.'"

And his reaction quickly sparked some guilt from Jessica, who also worried about how her and Justin's younger son Phineas, six, would react ...