Can you lose your home after being 1 day late on mortgage?

My biological grandma is extremely paranoid and always thinks the worse is going to happen. We had not spoken in several years and I told her that my husband and I had bought a house. She lives in an apt but immediately said "you do realize that you can lose your home after 1 day of being late on the mortgage!" She also told me that I could get my lights turned off after 1 day of being late (I was in the hospital recently and forgot the due date and this did not happen, in reality). Little does she know, that I own my home outright. But I don't think this is her business, or should I just tell her that? Is she correct about the 1 day late thing?
Added (1). she is extremely litigious and $ hungry and I dont really think she needs to know that no bank has a loan for me.

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