Lyrics for the show's theme song: Want you to meet the family that's known as the real McCoys / From West Vir-gi-nee they came to stay in sunny Cal-i-for-ni-ay / 'Ole Grandpappy Amos and the girls and boys of the family known as The Real McCoys / What a housekeepr Kate is, she's doin' what she enjoys / No gal can beat her when it come to looks and the same can be said 'bout the way she cooks for / Grandpappy Amos and the girls and boys of the family known as The Real McCoys / Livin' as good folks should live and happy as kids with toys / 'Ole Grandpappy Amos is the head of the clan, he roars like a lion but he's gentle as a lamb / His grandson Luke keeps a beamin' with joy since he made Miss Kate Missus Luke Mccoy / Sharing each other's sorrows, enjoyin' each others joys / Like all other families they quarrel and fuss but it a'int never serious with / Grandpappy Amos and the girls and boys of the family known as The Real McCoys
Writer Everett Greenbaum said Walter Brennan made racist and anti-Semitic remarks on the set.
In the promos for this series, the McCoys' farm is described as "20 miles northwest of the Los Angeles City Hall". This would be very close to where Walter Brennan was buried, at the Mission San Fernando Cemetery.
When the series moved from ABC to CBS for its sixth and final season, some of the continuing characters were dropped. For instance, Luke's wife Kate had died, and his brother Little Luke was packed off to boarding school and was not seen again.