There was some multigenerational synergy at the Grammy Awards on Sunday, as an 80-year-old Joni Mitchell performed with 40-something Brandi Carlile, and Tracy Chapman sang her hit song "Fast Car" with Luke Combs, the country artist who had a hit with his cover of it last year. Listeners call in to share their multigenerational music crossover tastes—what their 20- and 30-something kids have turned them on to, and what music "kids" in their 20s and 30s have gotten their parents into.