Does anybody have any experience with the stimulus checks at end of life?

This exact thing happened to me, if a few days off. My brother was still receiving his mail at his assisted living. Was hospitalized. Then was home on hospice for only days, and died. The stimulus was in his mail and was dated approximately a week before his death. As his POA and the Trustee of his Trust, had it been sent to me during the end of life care (I could not be there due to Covid and am in another city in our state) I could have deposited this. However, to me, the IRS is not worth MESSING with. I looked it up. There is an address to return the check to. Instructions are to mark VOID in the signature line and to return the check to IRS address in your area. Google the question and you will find this instruction.

I received one in my deceased brother’s name - he passed last June. I went on the US Treasury website to see what to do.
Treasury said return it.
That’s what I am going to do when things calm down with Covid.
You may be able to cash your family member’s, however. You can go to the US Treasury site & look at the FAQ’s.
My brother died intestate. I don’t want a flag on my taxes or be told I need to pay it back so “Return to Sender” for me.

I am sorry for your loss. May God bless you with grieving mercies and comfort during this difficult time.

It is their estate's money as it is dated before death.

However, I would not spend it until you finalize the estate, unless you need it for burial.