Why Meghan and Harry bizarrely DON'T have CUSTODY of their baby right now...

A bizarre royal law means that Meghan Markle, 37, and Prince Harry, 34, currently don't have custody of their own son, born on Monday.

The strange-but-true ruling also means that even Kate Middleton, 37, and Prince William, 36, also don't have custody over Prince George, five, Princess Charlotte, four, and Prince Louis, one.

Why? Because royal law states that custody of all royal minors actually lies with the Queen, 93.

Yep!

The law, called The Grand Opinion for the Prerogative Concerning the Royal Family, gives the Queen full control over the royal children and was introduced by King George I in 1717.

Royal expert Marlene Koenig told news.com.au: 'The sovereign has legal custody of the minor grandchildren.

'This goes back to King George I and the law’s never been changed.’

The law was introduced after King George I has a disagreement with his son, also called George.

Marlene added: 'He did it because he had a very poor relationship with his son, the future King George II, so they had this law passed that meant the King was the guardian of his grandchildren.'

To pass the law, King George put the question of custody to his judges and ten out of 12 judges ruled that the 'King’s right of supervision extended to his grandchildren and this right of right belongs to His Majesty, King of the Realm, even during their father’s lifetime'.

The law means that the Queen should have the final say on most parenting decisions including where and when the royal kids travel, where they go to school and how they are raised.

Whether or not Harry, Meghan, Wills or Kate actually ask her these things is debatable but, according to Marlene, her opinion is often sought.

Marlene explained: ‘When [Princes Harry and William] were little, Prince Charles asked the Queen if both children could fly on a plane together to Scotland, to which the Queen said yes,’ Marlene said.

‘Technically, they needed permission for travel. The Queen has the last word on parenting decisions like that.'

But, Marlene added that she believes the Queen will never feel the need to act upon her custody rights.

And we're guessing that the last things she would want to do is raise a newborn in her 90s!

'I would doubt that the Queen would interfere. [It’s] more of a formality,' she said.

However the law has come into force fairly recently with Harry himself - when his parents Diana and Charles separated.

Diana wanted to bring Harry and William to Australia, but couldn't because of the restrictions laid out by the law.

Another part of the law means that when parents of royal children divorce, children aren't included in the custody agreement because the Queen has custody.

When the Queen dies, custody of all royal minors will be transferred to Prince Charles, 70.

Would you want your grandmother-in-law having a say in how you raise your children?