The Gates family of Flint, Mich., has countless memories from Cornerstone Music Festival, as they've attended several times over the past decade. But they always get a laugh when telling of the time cows nearly trampled their tent. The Gates family was among thousands who turned out for a weekend of music and Christian camaraderie at the 26th annual Cornerstone Music Festival, which kicked off Monday. Organizers expect between 15,000 to 17,000 to show up through Saturday.