Meghan Markle and Prince Harry's son Archie could face huge royal restriction when he becomes a prince

Meghan Markle and Prince Harry may have stepped back from royal duties, but their one-year-old son Archie may still have major aspects of his life governed by the monarchy when he's older. 

The Duke and Duchess of Sussex opted not to bestow a royal title on their son when he was born, but his place in the line of sucession to the throne will change when his grandfather Prince Charles becomes king. 

Archie is currently seventh in line, but when he is bumped up to sixth, he'll be subject to the 2013 Succession of the Crown Act that rules members of the royal family must seek permission from the monarch to be married. 

At the age of 18, Archie will be allowed to chose whether he wants to go by Prince Archie, or use the His Royal Highness title, which his parents stopped using when they stepped down as working members of the royal family earlier this year. 

Regardless of his decision, he may still be required to request permission to tie the knot from either Charles or his uncle, Prince William, either of whom could be in power when Archie is old enough to marry. 

According to The Express, constitutional expert Iain MacMarthanne says Archie is likely to have the rule apply to him the same way it does his cousins, Prince George, Princess Charlotte and Prince Louis.

MacMarthanne explained the only way Archie might be freed from the obligation to ask if he can be married is if one of his three older cousins have children before him, bumping him down the line of succesion. 

Presently, Charles is next in line, followed by William and his three children, and then Harry and Archie.