One of the biggest challenges Barry Gibb has faced in his career was the death of his brothers Maurice and Robin, who were both members of the Bee Gees. This loss had a profound impact on him both personally and professionally. He also faced criticism for the Bee Gees' music during the disco era, which some saw as overly commercial and shallow. However, he continued to write and perform music that was true to his own vision, and he has remained a respected and influential figure in the music industry.