Prince Charles recently recalled his last conversation with the late Prince Philip in a new BBC One program, "Prince Philip: The Royal Family Remembers."

In the interview, the Prince of Wales shared that he called the Duke of Edinburgh at their Windsor residence on April 8, where they brought up their party plans for his 100th birthday by June, according to Daily Mail. And of course, Prince Philip got a quality response to his son.

While slightly trembling, the Prince of Wales said, "We're talking about your birthday," even though Prince Philip was not up for the idea. Being aware that his father has slight troubles with hearing, the son repeated a little louder, "We're talking about your birthday! And whether there's going to be reception!"

And In Duke's Response

And as the source would describe it as "typically pithy," the Duke responded, "Well, I've got to be alive for it, haven't I?"

Prince Charles replied, with which seemed to be their last conversation together, "I knew you'd say that!"

The program, to be released on Wednesday, September 22, is a tribute where the rest of the royal family recalled some of their fondest memories with Prince Philip before he passed away on April 9 at 99-years-old.

The writer and co-producer of "Prince Philip: The Royal Family Remembers," Robert Hardman, became the Prince of Wales and other family members' interviewer. He had given the outlet an exclusive insight into the show, where it became one of the most personal and intimate royal projects ever made.

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More Fond Moments With Prince Philip

Aside from the birthday conversation, Prince William also shared a hilarious anecdote regarding his grandfather. He went back to the time where the two stumbled upon a group of young walkers undertaking an expedition for their award.

And as the source described it to be the "Duke of Edinburgh's Award Scheme," William remembered, "He stopped and wound down his window and said, "Good morning. How are you getting on?"

A young man he questioned replied, "Jog on Grandpa!" The Prince even admitted that the stranger's response was even ruder than what he said, but his grandfather told him as soon as he rewound the window up, "The youth of today!"

The Prince found their whole conversation hilarious.

Even at the age of 99, the Duke's peaceful death still clearly came as a shock to his family.

His daughter-in-law Camille, the Duchess of Cornwall, also acknowledged, "It felt like the end of an era. They're a very difficult generation to live up to but I'm very proud and very pleased that I knew him."

"We were lucky to have him for nearly 100 years," her husband, Prince Charles, exclaimed.

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