Kym Marsh is distraught that her father's prostate cancer was caught too late to provide a cure.
The former Hear'Say singer's dad Dave discovered the disease was incurable and that it had spread to other parts of his body after delaying a check-up amid the Covid-19 pandemic.
She told The Sun: "Speed is crucial - it can make all the difference. Prostate cancer is treatable, when it's caught early."
Sharing the severity of Dave's condition, the Coronation Street star added: "It has been a very difficult time, I can't deny that, but we have always been very close as a family and so we have been able to talk together and plan for the future which is important.
"But the reality is that in Dad's case it has now spread to his pelvis, spine, ribs and left leg, which is of course bad news. At this stage, doctors are talking about it being incurable, but it is treatable and the hope is that they may be able to extend his life - but by how much, nobody really knows, and he is in discomfort."
Kym is now a host on the BBC's Morning Live show, and her dad appeared on the programme on Thursday to urge other men to get checked - pandemic or not.
"I think in his mind he has a target," she explained. "He hasn't really shared exactly what that is but he has done a lot of research himself - even though I told him not to - and he knows the statistics in terms of how long he might be able to fight this."
Dave admitted that failing to get appointments amid Covid-19 restrictions made him wary of going for a check-up, despite having suffered from a similar cancer in the past, saying, "I didn't want to cause a fuss."
The actress, who played Michelle Connor in the soap, went on to say that she didn't blame lockdowns for her dad's diagnosis - but urged those who do think they are at risk to make their health a priority.
"The NHS have had an awful lot on their plate the last 18 months and my dad knew that and so he put off going to the doctors as he didn't want to be a burden," she said. "He never dreamed it could be as serious as it's turned out to be for him."
Dave starts new treatment next week which he hopes can extend his life and allow him to walk Kym down the aisle when she marries boyfriend Scott Ratcliff. The couple announced its engagement last week.