Sir David Jason felt everything from "wonder" to "outright panic" when he received a letter from a daughter he never knew he had.
In 2022, the 'Only Fools And Horses' legend found out he may have a child he never knew existed for 52 years, which gave him a whole range of emotions as he tried to come to terms with the revelation.
Writing in his new memoir 'This Time Next Year', he recalling feeling everything from "wonder and amazement, through anxiety and heartache, to fear and outright panic”.
He said: "I’ve never experienced such a jumble of competing emotions. We were both feeling them. There was a lot of elation kind of, ‘Can you believe it?’ and, ‘What an amazing thing!’
"But there was an inevitable sense of distance too, and a pang of sadness for those missing years, all that lost time.
"So strange to feel this instant intimacy between the two of you, this obvious bond, and, at the same time, to be aware of this gap between you: so much common ground, and yet all that ground uncovered.”
The 84-year-old actor - who has daughter Sophie, 24, with his wife Lady Gill White - found out that he is the father of actress Abi Harris and grandfather to young Charlie.
Abi, 54, had an inkling David might be her biological father after hearing about her time with Jennifer - who starred in 'Doctor Who' and 1983 James Bond film 'Octopussy' - and she noticed she had a similar shaped nose to 'The Darling Buds of May' star.
She decided to write David a letter, quoting a line from Dylan Thomas' play 'Under Milk Wood', and asked if would take a paternity test, which he agreed to.
In his book, Sir David has revealed the letter, which reads: "To begin at the beginning, well actually, at my beginning. I wonder whether it has ever crossed your mind, as it has done with Mum and more recently with me, that you might be my biological father?”
She insisted she wasn't looking for financial support, but asked if the actor would "take an anonymous paternity test so that I can finally know the truth and let the matter rest".
Sir David continued: "You will be unsurprised to learn that my hands were shaking by now. What had I just read? I had to go back and read the whole thing again. And then I had to read it again. And then again after that.
“I have to say it really hadn’t crossed my mind that Abi Harris was my daughter – that my relationship with Jennifer Hill while we were in that production of Under Milk Wood in 1970 could have produced a child without me knowing about it.
“At no point in the nearly fifty years that had gone by since then had that thought had cause to enter my head.”
His wife was stunned by the news, but they both felt sympathetic towards Abi and her situation.
He added: "So naturally I should agree to do the test. And if the test came back positive, then we should meet Abi and open our arms to her. I am so grateful that Gill was so supportive and understanding about it all.”