Prince Charles is reflecting on his final conversation with the late Duke of Edinburgh

Prince Philip passed away in April at age 99.

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While opening the documentary “Prince Philip: The Royal Family Remembers”, which is set to air on Wednesday night, Charles recalls, “I was talking to him the day before he died, we were talking about his birthday coming up. I said (speaks loudly), ‘We’re talking about your birthday,’ because he was getting a bit deaf. And he said, ‘What?’ And I said, ‘We’re talking about your birthday and whether there’s going to be a reception.'”

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Revealing that the duke maintained his keen sense of humour until the end, Charles adds, “He said, ‘Well I’ve got to be alive for it, haven’t I?'” After a pause, Charles added: “I said, ‘I knew you’d say that!’ Anyway, it’s a happy memory.”

The BBC doc was originally intended to celebrate Philip’s 100th birthday

All of the Queen and Philip’s children and adult grandchildren will take part in the show, with many of them sharing sweet family memories. 

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Prince Philip’s long-serving staff will also share recollections of his extraordinary past.