Penny Lancaster's friend had coronavirus but had to be turned away from hospital because of the demand caused by the pandemic.
The 49-year-old star has heaped praise on the efforts of the NHS staff after her friend - who had been taken to the Princess Alexandra in Harlow, Essex - was treated by paramedics in an ambulance and at her home while suffering with the respiratory illness.
Speaking to The Sun newspaper, she said: "A friend of mine, who had Covid-19 and was in a bad way, was taken to that hospital recently.
"They said: 'You're young and you're not in a state as bad as some of them, sorry, we'll have to let you go, we don't have room.'
"They had to turn her away. That's how full they were. It's what it had come to but luckily the paramedics gave her the treatment she needed in the ambulance and back at home."
Penny - who married 'Maggie May' singer Sir Rod Stewart in 2007 - also paid tribute to the some hospital for the care they gave the couple's youngest son Aiden, now nine, after he fell from the top banister at their home to two years ago.
Admitting she feared he was "paralysed" from the terrifying accident, the mum revealed how delighted she was with the way he was looked after.
Explaining there were three paramedics on hand to take him there, she added: "When we got to the emergency room, there must have been at least eight people in there. It's unbelievable.
"There was no waiting around or scrambling around to find the right doctor. There were just eight people waiting in a room, ready to give world-class care.
"Rod was out on tour in America at the time. I didn't call him till we had some better news. The doctors and nurses were incredible. I was so confident they were making the right decisions."