The mysterious life of James Middleton, Kate's party-loving little brother who runs a marshmallow company

The INSIDER Summary:

James Middleton, 29, is the younger brother of Pippa and Kate, Duchess of Cambridge. 
After dropping out of college, he picked up a reputation for reckless partying.
Later, he started a cake business that ultimately failed. 
Now, he runs a custom marshmallow company - and seems to be settling down in a relationship.

Everyone knows Kate Middleton because of her dreamy royal wedding to Prince William. And everyone knows her younger sister, Pippa, because of the scene-stealing bridesmaid dress she wore to that wedding. 

But fewer people know about the youngest Middleton: 29-year-old James, who's making his way in the business world as the head of a 100% serious, personalized marshmallow company called Boomf. 

Here's a look at James's life both before and after his family became quasi-royalty.