In 1969, Robin left the group after feeling their new manager, Robert Stigwood, favoured Barry as the frontman.
This was to become a recurring theme in their history, with Robin and Barry having a difficult relationship.
Speaking of this to the Irish Times in 2020, Barry said: “Before we ever became famous were the best times of our lives.
“There was no competition; it didn’t matter who sang what.
“When we had our first No 1, Massachusetts, Robin sang the lead, and I don’t think he ever got past that; he never felt that anyone else should sing lead after that.
“And that was not the nature of the group. We all brought songs in; whoever brings the idea in sings the song.”