Legendary guitarist Eddie Van Halen had a serious health scare recently, forcing Van Halen to cancel all of their scheduled shows until next year. But the musician showed up to watch his son Wolfgang play bass at a Tremonti gig in Kansas City Wednesday night (Oct. 3), looking healthy and relaxed.

The 57-year-old guitarist underwent emergency surgery in August after suffering a severe bout of diverticulitis. Press reports blamed the health crisis on a fad diet called Master Cleanse, but the good news is that the elder Van Halen is expected to make a full recovery in 4-6 months.

Meanwhile, with his schedule suddenly open, Wolfgang Van Halen was free to accept the gig with Creed and Alter Bridge guitarist Mark Tremonti, who is touring to promote his solo album 'All I Was.' Wednesday night marked the first time the proud papa has seen his son with his new band -- the only other group he's played in professionally besides the mighty Van Halen.

"So glad my pop got to see the #Tremonti gig tonight in KC!" an excited Wolfgang posted to Twitter after the show.

The Tremonti tour is scheduled to run through Oct. 7 in the U.S. before wrapping up in San Antonio. The band then depart for Europe, where they will perform in the U.K., Holland, Germany and Italy.