7/25: U.S. officials: Russia has fired artillery into Ukraine; Parents overcome daughter's tragic death through her "bucket list"

The U.S. and Ukraine are accusing Russia of launching artillery attacks on Ukrainian troops from Russian soil and preparing to move more heavy weapons over the border. Over the past two weeks, half a dozen artillery barrages have already been fired from southern Russia; and, in our continuing series "On the Road," Steve Hartman meets Sandra and David Chesterman, a couple that's celebrating the life of their daughter Kristina in a very special way -- through her bucket list.