Complex sentence: In April 1969 Andy Williams, a close friend of Robert Kennedy recorded a version on his album "Happy Heart", and sang the song on his show over a year after Robert Kennedy's death.
Split into simpler sentences: In April 1969 Andy Williams, (who was, in fact, a close friend of Robert Kennedy) recorded a version on his album "Happy Heart". Williams also sang this song on his show over a year after Robert Kennedy's death.