Is losing an adult child worse than losing your parents?

I'm 35 years old, my parents and grandma are alive and healthy. I would hate to lose them. It would be earth shattering to me.

I still can't imagine losing them, not having them in my life. However I've heard if it's vice-versa (if my parents were to lose me, their oldest child or my 20 year-old brother), it's a lot more devastating. Is it? Both are losses, both are sadness, both live a big hole in your heart.

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Both leave a big hole in your heart. You involved losing a loved one.
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Then I've also heard that if my grandma lost me or any of her grandchildren, that would be enough to cause her a heart attack. She wouldn't be able to handle the news. I'll be grieving so much the day she dies. I still can't imagine losing her either.
Is losing an adult child worse than losing your parents?
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