[quote name='chris_b' timestamp='1475833340' post='3149039']
Mo did all the high vocal lines on Bee Gee records as well.
[/quote]
No, he didn't, Chris. Barry did the falsetto, Robin did the high lines with his unmistakable vibrato, and Maurice, whose voice was admittedly not as good as his brothers', did the choruses and harmonies. He only sings lead in a total of 2 or 3 songs in the whole of their back catalogue, IIRC. He was at his strongest as a multi-instrumentalist, and he was also the connective tissue between the other two brothers' rampant egos.