A devastated mum has been told her infant daughter has just weeks to live - after the baby was born with only half of her heart functioning.
Sienna Boylin was born on 24 January, weighing a healthy 7lbs 6oz - with mum Kelly High, 27, assuming she had a perfectly healthy baby girl.
But just three weeks and four days later, Kelly woke in the middle of the night to find her daughter struggling to breathe - shortly before Sienna started to turn blue.
‘We were faced with the choice of turning off her machines’
Mum-of-two Kelly, from Sprowston, Norfolk rushed Sienna to hospital, where she was resuscitated and stabilised.
But on February 19, Kelly was given the devastating news that Sienna had hypoplastic left heart syndrome (HLHS) - meaning that the left side of her heart had not developed properly.
Kelly, a stay-at-home mum to Sienna and her eight-year-old sister Maddison, said: "We were faced with the choice of turning off her machines and saying goodbye there and then, or trying a cardiac surgery to give us more time with her.
"Because the HLHS wasn't diagnosed until after she was born, it had already really damaged her heart valves - meaning her body was basically already shutting down."
But Kelly opted for more time with her baby daughter - and Sienna underwent a hybrid cardiac procedure on March 2, at just five weeks old, at Great Ormond Street Hospital in London.
The procedure involves widening the opening between the left and right atria - the upper chambers of the heart - and placing in a stent, in a bid to improve blood-flow from the heart through the body.
Kelly waited anxiously for seven weeks after the surgery - only to find out last week that it had not been successful.
And because of Sienna's young age, doctors say the hybrid cardiac procedure she underwent in March was the only option for her - and there is no more surgery to offer the youngster.
Now, Kelly is faced with the heartbreak of having to plan a funeral for her four-month-old daughter - after doctors told her Sienna has just weeks to live.
Kelly said: "It's been devastating. The wait to hear whether the surgery had worked was horrendous - and then we found out there was no more surgery available to her.
"It's just gutting. All we can do now is just make the most of every moment we have left with her.
"She's such a happy, bubbly little baby. You wouldn't know to look at her that she's got this life-limiting illness - which just makes it more heartbreaking."
Kelly is also questioning why Sienna's HLHS diagnosis was not picked up sooner - as it is a condition that can usually be diagnosed during pregnancy.
Kelly carried Sienna to full-term and gave birth at Norfolk and Norwich University Hospital at 41 weeks - after what she thought was a normal pregnancy.
So she was shocked to be told of Sienna's diagnosis with HLHS when her daughter was already almost four weeks old.
She said: "Doctors told me all the way through the pregnancy that everything looked healthy, and that she was growing really well.
"I even had two extra scans during the pregnancy because my bump was coming up a little small.
"My dad passed away from a heart condition as well, which is something I did tell doctors, because they ask you if there's any history of it in the family.
"I just don't understand how it could have been misdiagnosed all the way through my pregnancy. I definitely feel like it should have been picked up earlier."
Kelly now has to monitor Sienna's oxygen levels every morning - which are typically just 80 per cent when they should be between 95 and 100 per cent.
And Sienna requires three-hour feeds to keep the healthy side of her heart functioning.
But Kelly says she does not wish to dwell on Sienna's late diagnosis - and instead wants to focus on making precious memories for her two daughters during Sienna's remaining weeks.
She said: "We do have our scary moments, especially when I have to watch her sleeping because her breathing looks funny.
"But now we just want to move forward. I want to make the most of every minute, and focus on making fun memories for my two girls."
Kelly has set up a fundraising page to help her cover funeral costs for Sienna, as well as planning family days out while they still can.
She said: "The support has been overwhelming. I've been really surprised. It's so nice having so many people supporting us - I take comfort from it."
To donate, visit their fundraising page here.
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