Zion Foster has shared a touching tribute to his twin daughters after fiancée Jesy Nelson revealed they had been diagnosed with a rare genetic condition

Zion shared a photo of the twins in a stroller, with breathing tubes attached to their faces, and wrote on his Instagram Story: "Still smiling through all the challenges.

"Daddy loves you so much."

Jesy, 34, told how her daughters will "never walk" and have lost the ability to hold up their heads as a result of the condition.

She said in her emotional video: "The girls have now been diagnosed with a severe muscle disease called SMA type one. For those of you who don't know what SMA type one is, it's a severe muscular disease that a baby can get.

"It's done for Spinal Muscular Atrophy, which can affect, well it does affect every muscle in the body, down to legs, arms, breathing, swallowing.

"And essentially, what it does is, over time, it kills the muscle 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.

"When they assessed the girls at Great Ormond Street, we were told that they will never be able to walk and never regain their neck strength, so they will be disabled."

Nelson added that the babies have started having treatment and claimed that would have died without it.

She said: "And so the best thing we can do right now is to get the treatment, and then just hope for the best. So hopefully the girls have had their treatment, which you're so grateful for.

"Because if they don't have it, they will die."

Jesy explained that she has had to put her daughters on "breathing machines" and act as their nurse since the diagnosis.

She added: "The reason I wanted to make this video was because 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."

Jesy concluded that she hopes her daughters can "defy the odds" and explained she wanted to share their diagnosis with the world in the hope of helping other parents getting their children treated as soon as possible.