The mother-of-two, 33, looked gorgeous in a vibrant frock while attending the John Varvatos 11th annual Stuart House Benefit event in LA on Sunday (13 April).
Jessica tweeted back on 7 March that she'd reached her goal weight after following a Weight Watchers regime, telling Twitter followers: "To anyone who's afraid to go to meetings – don't be! I promise, that's what got me to my goal."
The bubbly blonde is a celebrity spokesperson for Weight Watchers after successfully using the programme to lose weight following the birth of daughter Maxwell in 2012.
She then used it again after the birth of son Ace last year.
As well as wanting to regain her pre-baby figure, the singer has been toning up ahead of her wedding to former American footballer Eric Johnson.
The couple have been engaged since November 2010 but two previously planned weddings have been postponed because of Jessica's two pregnancies in two years.
Jessica has been keeping mum on details of their third planned event but it's expected to take place this year.
Yesterday's Stuart House event was raising awareness of the programme created by the Rape Treatment Centre at Santa Monica's UCLA Medical Centre, which provides services for sexually abused children.
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