Jonathan Harris: On The Chemistry Of Will Robinson And Dr. Zachary Smith

"We needed each other. I'm no fool, I needed that young boy. He was very, very important to me. He was also a wonderful actor, I thought.  We needed each other and we used each other. I helped him a lot and he helped me a lot. I think we both came off sound and shiny, actually." 

-Jonathan Harris speaking candidly in a 1986 interview with Willam E. Achors, Jr. in The Lost In Space Encyclopedia II [p. 350]-