1. Alexandra Andresen, 19
Source: Business Insider
Like her sister, Katharina, Alexandra Andresen holds 42 percent of the family-owned company, giving her a net worth of $1.2 billion at just 19-years-old. Thankfully, neither Katharina nor Alexandra have been asked to run the business as Johan continues to maintain control, and Alexandra spends much of her time riding horses. She is a three-time junior Norwegian champion in dressage riding.