net worth of $250 million, but Ann Romney recently complained about having to release her tax returns as a part of her husband's campaign for the Republican nomination.

"You all know that he's been successful in business," she told a crowd in Miami earlier this year. "Unfortunately that was made abundantly clear yesterday when our tax forms were released."

Ms. Romney has credited horse riding with helping her to deal with multiple sclerosis, a pastime that most sufferers of the disease do not have access to.

As The New York Times noted in 2007, dressage horses can run in the seven figures and the saddles can cost thousands of dollars.

But even at those prices, Ann Romney won't tell her husband how many horses she owns.

“Mitt doesn’t even know the answer to that,” she laughed. “I’m not going to tell you!”