Complex sentence: The first real milestone for the band came in the spring of 2010 when they were involved in the "Rest In Sleaze festival", dedicated to the former lead singer Dave Lepard from Crashdïet, who had passed away.
Split into simpler sentences: The first real milestone for the band came in the spring of 2010 when they were involved in "Rest In Sleaze festival". Dedicated to the former lead singer Dave Lepard from Crashdïet, who had passed away.