Prince William turns the big 3-0!

>> for those of us who remember the day he's born, it's hard to believe but today mark as milestone for britain's prince william . he's turning 30 just months after his bride hit the big 3 -0 herself. michelle is at buckingham palace with more. good morning.

>> reporter: good morning. now the prince and wife, catherine, have both entered the decade of their 30s with another big year ahead of them. this is not just symbolic of growing up. it is very concrete as he inherits an enormous sum of money. he's the future king we watched grow from the very beginning. diana's first born, the almost impossible adorable toddler, his first day of school and first brushes with public life . then the devastation of his mother's loss. an unforgettable slow, stoic walk behind her casket. and of course this fairy tale marriage last year to his beautiful long-time love. today william has matured into a young man and is much respected for his modesty and dedication to service.

>> the adulthood for preeince william has cemented him as a proper grownup.

>> reporter: as a rescue pilot, he has saved lives. brother harry joked william is becoming middle aejed and boring and he will spend in big birthday quietly. reportedly kate has planned a dinner with their closest friends. but on this milestone for william also comes a fortune, the remainder of diana's estate set aside for him, said to total a around $10 million after taxes. he's said to have been receiving some of that five years ago, $450,000 a year. their combined waealth, $46 million.

>> he's not a lavish spender. he tries to live off the money from his father.

>> reporter: it's possible with william 's windfall, they might buy a country home as a private retreat. which brings up when we might see these two cuddling something in their arms which is not a puppy. the palace wouldn't say how much prince william will inherit today. it would be as much as $15 million. prince harry will receive the same amount when he turns 30. matt?