British-born Sex and the City star Kim Cattrall is the next celebrity to retrace her ancestry in BBC One’s Who Do You Think You Are?

Unlike many people who have done the show you had a specific aim to find out why your grandfather, George Baugh, abandoned his wife and three little girls in 1938. Why did you need to do this?
“I think it was because my mum and her sisters have never been fully able to grieve the loss of their father and what they missed growing up. Or acknowledge how strong they were and are, to have survived their upbringing in the slums of Liverpool during the 1930s, 40s and 50s after he deserted them.”

What you found was that George married again, bigamously, just one year later and started a second family in Manchester. How did that make you feel?
“I am terribly sad and I can’t forgive him for what he did. We also found pictures of his new family happily holidaying on the beach, while my grandmother dressed her children in rags, drank from empty jam jars and used newspapers for a tablecloth.”

What was it like telling your mum and her sisters the truth?
“It was the most difficult thing. It felt like I was ruining their last fantastic hope of what became of him. He was unremarkable except in his selfishness.”

But you have no regrets about the show?
“No. In the end it became a story not about my grandfather’s desertion, but my mother and her two sisters surviving it. Of that, I am profoundly proud and grateful.”

*Watch Kim in Who Do You Think You Are? on Wednesday, August 12 at 9pm*