(CNN) He had said he couldn't imagine life without her. As life would have it, he won't have to.

A husband and wife in St. Peter, a town about an hour south of Minneapolis, Minnesota, were married for 68 years but died just one day apart, their son told CNN.

Corinne Johnson, 87, died on November 24. Her husband, Robert Johnson, 85, followed soon after on November 25.

Their son, Brent Johnson, said his parents approached their deaths peacefully.

"They both knew what was coming and they didn't have any fear," he said. "They had both lived full lives and they were ready."

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