Mister Rogers' Neighborhood (1968)

Season 12: Episode 3

After a brief mention of the trouble he had zipping his sweater, Mister Rogers shows a handful of plastic pieces. He explains that these pieces are melted down and used to make dolls. Inviting viewers along, Mister Rogers visits a factory where dolls are made. Returning to the house, Mister Rogers talks about how dolls are made and people are born -- dolls are put together and people grow together. This leads perfectly into Everything Grows Together.