With Alaska Airlines, you can ask for miles to be transferred to your account.
I had to know my Mom's account number, DOB, address, etc, then I had to send a copy of my Mom's death certificate to the address they gave me. A copy is fine; didn't need the original
They transfer the miles in units of 1,000.
They showed up in my account as:
SPECIAL SERVICES
MEMORIAL POINTS
Thanks, Mom!