Prince William on road to the UK throne

London: The world watched as Prince William grew from a towheaded schoolboy to a dashing air-sea rescue pilot to a balding father of three. But as he turns 40 on Tuesday, William is making the biggest change yet: assuming an increasingly central role in the royal family as he prepares for his eventual accession to the throne.

That was clear two weeks ago when William took centre stage at the extravaganza concert marking Queen Elizabeth II’s 70 years on the throne, lauding his grandmother as an environmental trailblazer as he delivered a call to action on climate change.

“Tonight has been full of such optimism and joy — and there is hope,” he said, as images of wildlife, oceans and jungles were projected on the walls of Buckingham Palace behind him. “Together, if we harness the very best of humankind, and restore our planet, we will protect it for our children, for our grandchildren and for future generations to come.”

The world has watched William from his school days in London to his courtship of Kate Middleton at St. Andrews University in Scotland and their spectacular marriage at Westminster Abbey. He paraded before the cameras once again when he graduated from the Royal Military Academy Sandhurst, then went on to active duty in the Army, Navy and Royal Air Force.

Finally, he became a civilian air ambulance pilot before moving into full-time royal duties five years ago. His charities and causes — from mental health to the environment — have given hints of what sort of monarch he might one day be. —AP