Meghan Markle, 36, and Prince Harry, 33, are set to marry on Saturday 19 May at Windsor Castle.
Harry’s fiancée, who is three years his senior, will be the oldest royal bride in British history when the pair get married.
However, will the age gap affect Meghan and Harry’s relationship?
James Preece, a dating coach and relationship expert, says in some cases a man less mature than his wife “might not be ready to settle down”.
The Meghan and Harry age gap is “unusual for royalty,” he said of the difference in their ages.
“In most royal relationships, the man is usually older or their ages are similar.” For instance, Kate Middleton, 36, is just months older than Prince William, 35.
For some couples, the man being younger may ring alarm bells, he warned.
“If he hasn’t lived as interesting a life as the female then he might not be ready to settle down just yet.
This because “women tend to be more emotionally mature than men,” so they are in effect older than their years.
However, James said this would not be the case for the royal couple.
“In reality, as a Prince, Harry has lived a more exciting and interesting life than most.
“He has learned exactly what he wants in life and is more than ready to commit to Meghan.
Age was not so much a factor in the pair’s marriage – rather their “shared goals”, he said.
“He’s marrying her because she’s fun, young minded and full of energy.
“They have the shared goal of starting a family sooner rather than later, which will bring them even closer together.
However, not all experts are as positive about the couple’s prospects.
A handwriting expert said Meghan and Harry would have to “compromise” on their differences to make their marriage work.
