William, pictured at the controls of a Sea King helicopter

Coming of age: William, pictured at the controls of a Sea King helicopter, turns 30 today and has important decisions to make

And anyone who sees him and his wife together is left with the unshakable impression that this is a well-balanced couple, head-over-heels in love.

Yet according to well-placed sources within the prince’s circle, not everything is entirely rosy in paradise.

For members of the Royal Family, turning 30 is often a time of major transition – and, like his father before him, William has some very big decisions to make.