Born just weeks apart in 1926, Queen Elizabeth II and Sir David Attenborough have grown to hold a special place in the heart's of many.
Sir David, now 96-year-old, has spent much of his life bringing wildlife into our living-rooms with his outstanding, award-winning documentaries, spreading the message of conservation and the need to reverse humankind's impact on the world.
Meanwhile, the Queen has sat on the throne of Britain for over 70 years - reigning over the UK and Commonwealth during some of the most important years in the 20th and 21st century.
Attenborough made his first television appearance just a year after the Queen's coronation, taking to the small screen in 1954 with the BBC documentary Zoo Quest.
Seven decades on the biologist, natural historian and activist has become perhaps the most recognisable face of conservation and leader in bringing the world's attention to the plant and wildlife catastrophe.
Are Sir David Attenborough and the Queen friends?
Sir David first met royalty in 1958 while he was working at the BBC as controller. As part of a tour, the naturalist met the young Prince Charles and Princess Anne, introducing them to a cockatoo, Cocky. However, the beloved documentary maker's relationship with the monarchy hasn't always been cosy.
In his role as BBC controller, Attenborough oversaw everything that was aired. In 1969, despite Prince Philip agreeing to open up Buckingham Palace's doors to a filming crew, Attenborough was uneasy about it being broadcast. According to the author Ingrid Seward, he said: "You're killing the monarchy, you know, with this film you're making. The whole institution depends on mystique and the tribal chief in his hut.
"If any member of the tribe ever sees inside the hut, then the whole system of the tribal chiefdom is damaged and the tribe eventually disintegrates."
Despite the controversy, Sir David and the monarchy reportedly began to grow close thanks to their charity work and shared passion for wildlife.
For services to television, Attenborough was knighted in 1985 and between 1986 to 1991, the environmentalist worked closely with the Queen to produce her Christmas addresses to the nation.
In more recent years, as green-causes have become more prominent in the monarchy's work, the Queen awarded Sir David with the Order of Merit - a personal gift of the monarch for exceptional distinction in the arts and sciences. Attenborough now collaborates with the Queen's grandchildren Prince Harry and in particular Prince William's The Earthshot Prize.
Sir David and the Queen now enjoy a cordial relationship. The duo are frequently pictured together at plant and wildlife events and the naturalist has been heavily involved n the monarch's Platinum Jubilee appeal to plant a tree for The Queen's Green Canopy.
