No, they are not related. But they were both on the Tonight Show with Johnny Carson!
Elva Miller (1907-1997) was a 59-yr old grandmother in 1966 when she cut her first album, "Mrs. Miller's Greatest Hits", which sold 250,000 copies in just two weeks. Her memorable rendition of "Downtown" made it onto the Billboard hit single chart. And rightly so--it's a classic!
Herbert B. Khaury (1932-1996), aka Tiny Tim after the Dicken's character, sang and played the ukelele in the '60s. His is best remembered for his high falsetto and his rendition of "Tip Toe Through the Tulips".