Why summer is the right time to feed your passion 

For many, summer means time off and relaxation. But Angela Duckworth, author of the New York Times best-selling book, "Grit," says it's also a perfect time to develop interests. The University of Pennsylvania psychology professor found that grit, which she defines as a combination of passion and perseverance, is key to potential success, no matter what season. Duckworth joins "CBS This Morning" to offer practical tips for feeding your passions.