Nearly forgotten, and that might not be a bad thing, from the Brady franchise was their Brady Bunch Variety Hour from the late 1970s. It was awful, although Henderson, and to a lesser extent Greg (Barry Williams), Marcia (Maureen McCormick), and "Fake Jan," Geri Reischl, were quite good as they worked their way through show tunes.
Here's the "Stars Medley" from the Variety Hour. Watch as Mike Brady (Robert Reed) embarrasses himself. And you'll see Alice (Ann B. Davis) with, gasp, Rip Taylor as her boyfriend. What happened to Sam the Butcher (Allan Melvin)? We all know that he "delivered the meat." They were perfect for reach other. Such a shame.
Best of all, though is the conga line with Carol Brady, Milton Berle, and yes, Tina Turner.
File this video under it's-so-bad-it's-a-work-of-genius.