Rumored mommy-to-be Ashlee Simpson sported more than a smile when she recently stepped out -- looking noticeably larger up top! The skinny singer was spotted with a much a larger chest, reports the New York Daily News, which might be explained by her unconfirmed pregnancy.

"It's probably just a great bra, like any girl's secret," says her rep, responding to questions surrounding the newly busty star.

Baby questions were raised after Simpson began sporting an engagement ring from rocker beau Pete Wentz. Although Ashlee's team insists that no date or location have been set, it's circulating that the lovebirds plan to tie the knot in a Santa Barbara ceremony at the end of the month.

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