Often when successful rock bands lose a key member, they can't maintain their level of success and popularity, but there are notable exceptions over the years that not only maintained their fan base, they sometimes got much more successful....Take AC/DC, who, after the death of singer Bon Scott, hired Brian Johnson, and proceeded to record the second best selling album of all time: "Back in Black"...take Fleetwood Mac, who started out as a hard core blues rock band led by Peter Green. Green became mentally ill, and John McVie and Mick Fleetwood brought McVie's wife Christine into the band, and hired Lindsey Buckingham and Stevie Nicks, and became one of the biggest bands on earth....mental illness also took Pink Floyd member Syd Barrett, then they hired guitarist David Gilmour, and the remaining members galvanized to produce some of the greatest albums in rock history.....here are more bands that weathered the storm of losing key members, including Van Halen, the Pretenders and the Stones.... https://ultimateclassicrock.com/lineup-changes/