Former Little Mix star Jesy Nelson explained how her twin daughters might never be able to walk after a medical diagnosis. View this post on Instagram Instagram PostNelson took to social media to share with her fans how her twin daughters, Ocean Jade and Story Monroe, have been diagnosed with a rare genetic condition called Spinal Muscular Atrophy (SMA), which is known to be the most severe muscular disease.In the video, she said, "After the most gruelling three, four months, and endless appointments, the girls have now been diagnosed with a severe muscular disease called SMA type 1."Jesy Nelson added, "Essentially, what it does is, over time, it kills the muscles to the body, and if it's not treated in time, your baby's life expectancy will not make it past the age of two."Her daughters, whom she shares with musician Zion Foster, have not been showing as much movement, and it has been a struggle to feed them. The twins, who were born prematurely last May at 31 weeks, have been assessed at the Great Ormond Street Hospital in London.“We were told that they will probably never be able to walk and never regain their neck strength, so they will be disabled."“The best thing we can do right now is to get treatment and then just hope for the best. Thankfully the girls have had their treatment, which I’m so grateful for because if they don’t have it, they will die.”Jesy Nelson explained why she wanted to talk about it: "The reason I wanted to make this video was that the last three months have honestly been the most heartbreaking time of my life. I literally feel like my whole life has done a 360."She added that she is sharing the story to raise awareness and help other children get diagnosed as soon as possible. Jesy Nelson also believes that her daughters would "defy all the odds" and will fight this.