04/14/2003 at 01:00 AM EDT
has already made it big. After kick-starting the new millennium with Legally Blonde
, the 27-year-old actress upped her per-picture asking price from $1 million to $5 million and proved more than worth the investment when last year's Sweet Home Alabama broke box office records with a $37.5 million opening weekend. That gave her the clout to walk away with $15 million for Legally Blonde 2: Red, White & Blonde
(out July 2). But now, just weeks after wrapping the sequel, the Tennessee-born actress whom her mother, Betty, famously dubbed "Little Type A"—hence her Type A Films production company—appears to have gone on to even bigger things. No, not more comparisons with Julia Roberts
. More like bigger clothes. As an associate of Witherspoon's told a source, her rounded tummy means that 3-year-old Ava—Witherspoon's daughter with her husband of three years, Igby Goes Down star Ryan Phillippe
, 28—is going to have a sibling. Neither Witherspoon nor her rep will comment on the pregnancy reports. But just in case, a few words of advice to the costume designer on Vanity Fair
, the 19th-century period piece Witherspoon is scheduled to start shooting this summer in the United Kingdom: Empire waists are good.