In retrospect, mine has been having senior moments since about your mom's age. She has long been one to multitask, and think of 12 things at once. She finds herself thinking- perhaps an extra cup of rice with Sunday's dinner; I wonder if the radiators need bleeding; I should really call the stock broker; when is uncle XX due back from vacation so I can offer to run some new milk, eggs, butter etc to their home so they don't have to do a grocery run when they get in at god knows what hour; who is this mayoral candidate; all at once. She can't remember who she told what to, and if there is a deviation from her normal routine, expectations which she didn't think up or agree with in principle, she will have a hard time embracing it.
we have done the following-
to the extent that there are things which are to be calendared, I make sure that they are actually written on her calendar.
we've put in place certain belt and suspenders measures. Spare keys here and there. an extra land line, a spare key to the house, and a $20 in the butter dish in the fridge in the garage (which opens on a combination).
we top up the gas in her car whenever we see her.
we have the phone, gas, electric, etc alert us if bills are overdue.
we hand hold when it comes to technology, or difficult elections i.e. prescription drug coverage selections.
We started off by saying since she has our little one over sometimes, belt and suspenders measures are necessary as he has been known to say, drop keys in a snow drift. This was a comfortable way for her to accept the help (it wasn't about her failing abilities, it was about safeguarding her from our then toddler's antics) she has been good at recognizing that she needs the help. she is appreciative for the assistance.
Best to you and yours,
F. B.