Supermodel Maggie Rizer only gave birth to her daughter Cecilia Kathryn nine weeks ago , but the mother-of-three is already back to her trim and toned self . The 37-year-old fashion veteran sported a tiny string bikini as she posed with her two-year-old son Quinnlann Clancy for a sweet snapshot , which she shared Monday on her Instagram account . 'Boogie boarding with my baby , ' she captioned the image . And online commenters could n't help but note how fit Maggie looks only a few months after she and her husband Alex Mehran welcomed their first daughter into the world . Beach body : Supermodel Maggie Rizer donned a string bikini while playing with her two-year-old son Quinnlyn Clancy on the beach - just nine weeks after she gave birth to her daughter Cecilia Kathryn . Bundle of joy : The 37-year-old shared this precious baby photo to announce the birth of her third child and first daughter on February 9 . 'That body is right back ! ' one Instagram user posted , while another added : ' I . Just . Do n't . Understand . [ sic ] ' Maggie thanked her commenters for being 'very kind ' before noting that she takes great care over which images she chooses to share on her account , saying : ‘ I post carefully ! ’ But one fan insisted on giving the model credit for getting her amazing body back into such great shape so quickly , writing : ' @ maggierizer there 's not enough careful in the world to make me look like this even though I have ONE kid and she 's almost two . You are killing it ! [ sic ] ' And Maggie has been working hard . Two weeks before her family vacation she shared a picture of herself on a Pilates reformer . 'Ca n't be a slacker forever I guess , ' she captioned the photo of herself working up a sweat . Happy family : Maggie posed next to her husband Alex Mehran to celebrate their newborn 's 'first trip to the beach ' Date night : Maggie and Alex were pictured enjoying a romantic dinner later that night . Maggie and Alex , who also have a three-year-old son named Zander , are spending time with their family , including their newborn at an unidentified tropical destination . Another Instagram snapshot , which was also posted yesterday , shows Maggie sporting patterned shorts and a pink tank as she poses next to Alex , who is holding their baby girl . 'Cecilia 's first trip to the beach ! ' she wrote . Later that night , Maggie shared a picture of her and her husband enjoying wine and a glass of something bubbly during a romantic 'island ' dinner . Maggie , who announced Cecilia 's arrival into the world with a precious Instagram photo on February 9 , continues to chronicle her children 's adventures and their precious family moments on the social media site . Getting toned : Two weeks before her beach vacation , Maggie shared this photo of herself working out on a Pilates reformer . Pretty in pink : Maggie and Cecilia donned matching pastel outfits for Easter . All bump : Maggie showed off her growing belly with a selfie she took in January . Maggie rarely models but remains in demand , despite having moved to San Francisco for her husband 's work . She was last seen on the catwalk in September 2014 at Michael Kors ' New York Fashion Week show . Though her pregnancy was not public knowledge at the time , she would have been four months ' pregnant - a point at which most expectant women start to show a small bump . Maggie , who originally hails from New York State , was one of the world 's most popular models in the late Nineties and early 2000s . She stopped modeling in 2004 after it emerged that her stepfather , John Breen , who had been handling her finances , gambled away her entire fortune . Her professional earnings alone were estimated to be over $ 7million , though she also lost inheritance left by her biological father , Kevin Rizer , after his death from AIDS when she was 14 . Since the loss of her father - her parents divorced when she was a baby when Kevin announced that he was gay - the model has been a staunch AIDS awareness activist .
The 37-year-old welcomed her first daughter Cecilia Kathryn into the world on February 9 . Maggie and her husband Alex Mehran are also parents to two sons , three-year-old Quinnlann Clancy and two-year-old Zander . The parents are enjoying a beach vacation with their three children .