The Waltons was one of the top TV shows of the 1970s, and two of its most beloved characters were the "Walton" grandparents.

Playing the wholesome "Grandpa" and "Grandma" were stars Will Geer and Ellen Corby. But that all changed in The Waltons season 7, when "Grandpa" suddenly disappeared from the show.

Why did "Grandpa Walton" leave The Waltons?

As it turns out, tragedy struck The Waltons just after season 6 finished in 1978. Three weeks after the season finale, actor Will Geer, who played "Grandpa Zebulon Tyler Walton," passed away at the age of 76.

Sadly, Geer died on April 28, 1978, in Los Angeles with his family at his bedside. His cause of death was a respiratory ailment, according to The New York Times.

Faced with the decision of recasting "Grandpa" or paying tribute to Geer, The Waltons chose to write the actor's death into the show.

The season 7 premiere announced the loss of "Grandpa" and the family paid their respects in the episode.

On The Waltons, his gravestone was adjusted to the show's time period, but it matched Geer's age, reading: "Zebulon Walton: 1865-1941."

The Waltons: "Grandpa" actor Will Geer died in 1978.

The beloved star's final Waltons episode was the season 6 finale. In the episode, "Grandpa" was able to reunite with his wife, who had been absent after actress Ellen Corby suffered a stroke in real life.

Like the loss of Geer, Corby's health incident was also written into The Waltons. "Grandma" was treated as a stroke survivor in her remaining seasons on the show.

Geer had enjoyed an acting career that dated back to the 1930s, and he's remembered for his work in Jeremiah Johnson and as a film, TV, and stage character actor.

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