From their Wikipedia:

Lon & Derrek Van Eaton were an American vocal and multi-instrumentalist duo from Trenton, New Jersey, consisting of brothers Lon and Derrek Van Eaton. They are best known for their association with the Beatles through the brothers’ brief stint on Apple Records, and for their subsequent session work in Los Angeles for producerRichard Perry. As well as recording their own albums, during the 1970s they appeared on releases by artists including George Harrison, Ringo Starr, Harry Nilsson,Carly Simon, Martha Reeves and Art Garfunkel.

Lon and Derrek van Eaton recorded critically acclaimed records for Apple Records during the 1970s, but commercial success eluded them. They did, however prosper as session musicians working with former Beatles George Harrison and Ringo Starr.

Apple Records Discography

Discogs discography

Allmusic review of the 1972 Apple Records debut album, Brother (produced by George Harrison, with Ringo Starr on drums.)