It depends on how old the grandparent is. You can apply for life insurance up to the age of 72, but it will usually be very expensive. Also, the grandparent needs to be fully in his right mind when he/she is signing the contract papers for life insurance. Your grandparent will be the policy holder and will have to appoint a beneficiary. You could find out life insurance rates for a grandparent on aggregator websites that offer free life insurance quotes.
Disclaimer: I work for AccuQuote and this is my personal opinion.
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