Prince Charles has long shared a deep and touching connection with his two sons, Prince William and Prince Harry.
Born in 1982 and 1984 respectively, the boys are not just Charles' heirs; they've long been two of his greatest supporters.
From championing causes the Prince of Wales spearheaded in his younger years, to promoting their father's best work, William and Harry have a clear respect for their dad.
But long before they were standing at his side as senior royals (and before Harry stepped down from that role), the brothers were simply Charles' boys.
The boys were just 15 and 12 respectively, when their mother Princess Diana died in a car crash, and in the wake of such a devastating loss, Prince Charles has always put William and Harry first.
"One of the hardest things for a parent to have to do is tell your children that your other parent has died. How you deal with that, I don't know," Prince Harry explained in the 2017 BBC documentary special Diana, 7 Days.
"But he was there for us. He was the one out of two left. And he tried to do his best and to make sure that we were protected and looked after. But he was going through the same grieving process as well."
We've dug through the royal archives to uncover some of their sweetest father-son moments through the decades, from the 1980s all the way into the princes' teen years.
From family holidays to early royal events and adorable candid moments, these pictures really show the three princes' incredible connection.
Scroll through to see some of the most touching photos of Charles, William and Harry from the archives.
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