Here’s a great find thanks to our friend, Ken! Cheryl guest-starred on a short-lived series, “David Cassidy Man Undercover” in 1978.
Watch for four fleeting appearances (with dialogue) at 14:24,17:54, 31:30, and 37:22.
DAVID CASSIDY: MAN UNDERCOVER
Episode 6 RX for Dying (Originally aired on 21 December 1978)
Daktari TV Show 
I recently bought the fourth series on DVD….and I really miss Jack!!! He, together with Mike and Paula, especially when Paula is a bit touchy….that was fun.
I´m always happy, that Cheryl as one of our heros is still with us.
I agree, I wished they had developed that relationship more.