Prince Charles has praised his father Prince Philip's energy as "astonishing" in a tribute.
The Duke of Edinburgh died peacefully at Windsor Castle this morning aged 99.
His oldest son told the BBC: "Well you know he didn't suffer fools. So if you said anything that was in any way ambiguous - he'd say 'make up your mind!'
"Perhaps it's made one choose your words carefully. He was very good at showing you how to do things, instruct you in various things."
Charles added: "His energy was astonishing in supporting my mama, and doing it in such a long time.
"What he's done, amounts to an astonishing achievement, I think."
Princess Anne said: "I think I will best remember him as always being there.
"And a person you could bounce off ideas, but if you were having problems you could always go to him and know that he would listen and try to help."
All four of the Queen and Prince Philip's children spoke to the BBC about their father.
Prince Edward said: "My father was always a great source of support and encouragement, and guidance all the way through, and never trying to curtail any of the activities or anything that we wanted to try and do but always encourage that.
"I will always remember and thank him for that."
Prince Andrew, said: "Like any other family at the time, your parents went out to work in the day.
"But in the evening, just the same as any other family, we would get together, we would sit on the sofa as a group and he would read to us."
A statement from Buckingham Palace, released at midday, said: “It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh.
"His Royal Highness passed away peacefully this morning at Windsor Castle. Further announcements will made in due course.
"The Royal Family join with people around the world in mourning his loss."
Philip will lie in rest at the castle but he will not have a state funeral in line with his final wishes.
The funeral arrangements are codenamed Forth Bridge, after the Scottish landmark and Unesco World Heritage Site.
