On December 14, Lajon Witherspoon (Sevendust) joined Mark Tremonti (Creed) onstage during his “Tremonti Sings Sinatra” show at the Walt Disney Theater at the Dr. Phillips Center for Performing Arts in Orlando, FL. You can see some fan-filmed footage of the duo performing a cover of Donny Hathaway’s “This Christmas” together below: View this post…