So someone's passing can be enough to cause your own death?

My family and I are grieving two deaths now. My 92 year-old great-grandmother just passed away only 3 days after receiving the news of my grandfather's (age 64) passing of cancer. He was the youngest of 4 children and the only male; my great-grandparents' only son.

She was a healthy woman, had no pre-existing conditions at all and could've lived a bit longer. We were told she entered a state of total shock and it was too much for her to handle. Is is a rare type of death, you dying shortly after someone else's passing?

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11 mo
Even though she was elderly, her death was still suddenly and unexpected. As soon as grandpa died, she dies in just 3 days.
So someone's passing can be enough to cause your own death?
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