I think Stevie Nicks actually got most of the publicity from Fleetwood Mac. She did have a very unique and amazing voice. She also had a bit of a cult following, even appearing in the American Horror Story series in recent years. But I always liked Christine McVie's voice better. Beautiful Child is a wonderful and touching song, but Songbird makes me tear up every time in part because of McVie's angelic voice.
That being said, when the two of them sang in harmony, it's what I hope heaven sounds like.
RIP.