<human>: My mom worked as a caregiver for my grandma for five years while my grandma was homebound. A few months ago my grandma went into the hospital for a month, then passed away. This all happened somewhat suddenly. 

Our family announced her death in the local newspaper, and many friends from her church attended the funeral. BUT my grandma still receives birthday/Christmas cards from people that hadn't visited her recently, and are unaware that she passed away. My family has never been overly 'formal' so we are unsure of what to write/how to respond.

My uncle [49M] lives in my grandma's house, and my mom visits him often and that's when she sees all the cards. My mom handled all the cards my grandma got before she died, so she feels like she has to respond to them now still. She is trying to figure out some message to send back in a card. Ignore them? Send another card in return to inform them of her death? These are acquaintances and in some cases grandma had not seen them in many years. I appreciate any advice/recommendations that you have. Thanks.

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<bot>: Mom was my grandma's caregiver for 5 years. Grandma died and still receives cards, unsure how to respond.