A mother has revealed how her baby's feet turned people after developing an inflammatory syndrome with the coronavirus.
Lauren Grant's daughter Madelyn, then five months, from Ohio, caught the infection in late January 2021 after her four-year-old sister Emma brought it home from nursery.
With the whole family testing positive, they isolated for 10 days, before sending the children back to nursery.
Grant, 25, received a call on 2 February saying Madelyn's hands and feet had turned purple.
Madelyn was rushed to a hospital, where her heart rate reached up to 275 beats per minute (bpm), with 80bpm to 160bpm considered normal for her age.
The otherwise healthy baby was diagnosed with multi-system inflammatory syndrome, a rare but recognised complication of the coronavirus in children.
After spending nine days in hospital receiving intensive treatment, Madelyn was finally allowed to go home.
Nearly a month on, Grant is speaking out to urge people to "take this virus seriously", even if you are young and healthy.
Grant, a nurse, tested positive for the coronavirus on 20 January after she started to feel unwell.
Her two children and husband also came down with the infection, with Madelyn enduring mild congestion, fatigue and irritability.
Madelyn returned to nursery after isolating, only for Grant to receive a worrying message about her daughter's hands and feet.
"I was definitely panicked," Grant told Yahoo UK. "I was thinking she wasn't getting enough oxygen to her feet and legs.
"I knew when I picked her up she was breathing harder than she normally would so I took her to do the ER [emergency room]."
Madelyn tested positive for the coronavirus at hospital, demonstrating she had not cleared the infection during the family's at-home quarantine.
"She had a high heart rate, a very high white blood [immune] cell count and high inflammatory markers," said Grant.
"She was very feverish. She did have a little bit of a rash on her legs."
Watch: Coronavirus can cause inflammatory syndrome in children
Madelyn was diagnosed with multi-system inflammatory syndrome on 3 February.
Grant, a nurse who works with adults, had briefly heard about the syndrome in the news, but was not particularly familiar with its complications.
Madelyn was transferred to the main campus at the Cleveland Clinic Children's hospital.
"Her heart rate was 245bpm," said Grant. "At one point it went to 275bpm.
"She was struggling to breathe, grunting, she wouldn't open her eyes."
Madelyn was moved to paediatric intensive care, where doctors administered drugs to bring her heart rate down.
To combat the multi-system inflammatory syndrome, the youngster was given intravenous immunoglobulins; antibody proteins that work to fight off an infection.
Medics also administered steroids, blood thinners and diuretics.
"She was also on a couple broad-spectrum antibiotics to make sure it wasn't a bacterial infection," said Grant.
With Madelyn critically-ill, her parents could not help but think the worst.
"My husband and I were just sobbing," said Grant. "We really thought she wasn't going to live."
Around 24 hours after her admission, however, Madelyn "started to turn a corner".
"She started smiling again, she was happier, she was moving around a little bit more," said Grant.
Now home, Madelyn's hands and feet are still cool to touch, and turn a light purple at times.
It is unclear whether the ordeal has caused any lasting damage that may affect Madelyn's development, with coronavirus-related multi-system inflammatory syndrome being a relatively new phenomenon.
"She will have follow-ups with cardiologists, haematologists and rheumatologists," said Grant.
While Madelyn has overcome the coronavirus, and is hoped to have some immunity against the infection, it is unclear if she could develop multi-system inflammatory syndrome again.
"That's what’s scary about this," said Grant.
When Madelyn was first brought home, her mother was "scared to go to sleep at night".
"It's been quite a terror," said Grant.
The mother-of-two has connected with other parents who have been through a similar ordeal via Facebook support groups.
"We're lucky we caught this when we did it," said Grant. "I've talked to parents who've had children die from this."
The nurse, who has been vaccinated against the coronavirus, is speaking out to raise awareness of the seriousness of the pandemic.
"Wear a mask, keep distancing yourself from others, no large gatherings," she said.
"Trust your instincts. When you go to the doctor and your child has had COVID [the disease caused by the coronavirus] and they feel very unwell, make sure your doctor orders lab tests to check for these inflammatory markers.
"Sometimes it gets written off as a flu or another virus."
What we know about the coronavirus-inflammatory syndrome
Early research suggests the coronavirus is mild in four out of five cases, with children in particular rarely developing serious complications.
Nevertheless, NHS doctors were told early in the outbreak to look out for signs of "multi-system inflammation".
The warning came after intensive care units in London saw eight children with unusual symptoms, some of whom tested positive for the coronavirus.
Medics have likened the mysterious inflammation to atypical Kawasaki disease; a rare condition that usually affects children under five and causes blood vessels to become inflamed, leading to heart complications in around a quarter (25%) of patients.
Common symptoms include a rash, fever, and red hands and feet.
Kawasaki disease is thought to come about when the immune system over-reacts to an infection. Left untreated, the heart complications can be fatal in 2% to 3% of patients.
Scientists from the New York University Grossman School of Medicine have previously noted "significant clinical overlap exists" between Kawasaki and the coronavirus-related inflammatory syndrome.
The latter, however, "has been characterised by more widespread systemic inflammation and higher rates of acute complications, including cardiogenic shock"; when the heart suddenly cannot pump enough blood to meet the body's needs.
The inflammatory disorder has also been likened to toxic shock syndrome (TSS).
Often associated with tampon use, TSS is a medical emergency that can lead to fever, flu-like symptoms, nausea, vomiting and difficulty breathing.
Experts have warned these symptoms are a sign the body is overwhelmed as it tries to fight an infection.
While the inflammatory syndrome may sound alarming, the vast majority of children are said to recover with hospital treatment, with experts repeatedly stressing there is no need to panic.
The Royal College of Paediatrics and Child Health previously advised parents call 999 or take their child to A&E if they:
Become pale, mottled or abnormally cold to touch
Pause in their breathing, have an irregular breathing pattern or grunt
Have severe breathing difficulties, while becoming agitated or unresponsive
Go blue around the lips
Have a seizure
Become extremely distressed, confused, lethargic or unresponsive
Develop a rash that does not disappear with pressure, like when pressed under a glass
Have testicular pain, especially teenagers
Watch: Can you catch coronavirus twice?