But the actress, whose mom Amy suffers from a terminal illness, was turned down.
The 39-year-old former glamour model was distraught when she found out her mother was diagnosed with idiopathic pulmonary fibrosis - a type of chronic lung disease which causes a progressive and irreversible decline in lung function - and immediately offered to donate one of her healthy lungs in a bid to prolong her life.
Amy turned down Katie’s offer, expressing concerns about her daughter and her five children.
She recalls: “I said no, you’re not going to do that. You’ve got to think if, by any chance, it went wrong, who’s going to look after your kids? You’ve got to think about your children, not me, and what’s going to happen to them. Of course, I was so touched at her offer.
“But Kate is my child, not the other way around. I have to protect her. So there will be no lung transplant from Kate. I can’t allow it.”
The same time her mother was diagnosed, Katie had to cope with finding out her joller husband Kieran Hayler had been at it again.
She admitted to receiving therapy to deal with the fact that Amy is going to die.
She said: “It was the best thing I did, what it is going to do is that I’m going to learn to cope with my mum’s [death] before she goes. I’m going to go until my mum goes to keep me strong.”
She’ll be joining 40 000 runners in the gruelling London Marathon on 22 April to raise funds for the British Lung Foundation, which has supported Amy.
The cause of IPF is unknown and there is no cure. The disease causes scarring of the lungs, making it difficult to breathe.