Pay Dirt is Slate’s money advice column. Have a question? Send it to Kristin and Ilyce here. (It’s anonymous!)

Dear Pay Dirt,

My wife and I are in our mid-50s, and we have two kids who are both now in college. Last week the neighbors asked to speak to my wife and me. When we met with them, they showed us some shocking footage from their security cameras.

The footage revealed my mother-in-law, “Gladys, “peering into their windows and trying the handle of their front door as well as her roaming through their backyard and trying to get in through their patio door. We were embarrassed as hell and apologized.

Gladys is 80 and moved in with us a few months ago after she got priced out of her rental property.It’s not working out to put it mildly. Within a week of coming to live with us, Gladys decided that our neighbors—the ones who eventually showed us the footage—were spying on her and had bugged our phones to keep tabs on her. The neighbors have never even met my mother-in-law. Plus, they are frequently absent, as they run their own business and travel to see clients. When we spoke to Gladys about what the neighbors showed us, she asserted that she was looking for “evidence” and accused us of being “on their side.”

Later that evening, I told my wife we needed to get her mother screened for dementia and to look into a care facility for her. My wife thinks we just need to keep a closer eye on her and install some of those alarms that go off when a door inside a house is opened so we’ll know if she tries to leave. What can I do to convince her that her mother’s issues are beyond our ability to deal with?

—Dementia Doesn’t Get Better

Dear Dementia Doesn’t Get Better,

You already sense what’s happening here, and your instincts are likely correct. What you’re describing—paranoid delusions about neighbors spying, bugged phones, gathering “evidence,” accusing you of being complicit—are classic symptoms of cognitive decline. This is not a behavior problem. This is a medical situation that needs immediate attention.

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I do want to call out the possibility it may not be dementia. Sudden paranoid behavior in the elderly can also be caused by a urinary tract infection, medication side effects, vitamin deficiencies , delirium triggered by an underlying illness, or depression. The good news is that some of these causes are entirely reversible if caught early. That’s all the more reason to get Gladys evaluated immediately rather than waiting—early intervention could preserve cognitive function she still has, or even reverse what’s happening entirely.

Which brings us back to your wife’s solution: door alarms are not a solution. They’re at best a bandaid, a way of managing symptoms of something that will only progress without proper diagnosis and care. Think about it: Within weeks of moving in Gladys was trespassing on your neighbors’ property. That’s not something a door chime fixes.

I feel for your wife. Watching a parent decline is devastating, and denial is a natural response. But the kindest thing you can do for Gladys right now is get her in front of a geriatric psychiatrist or neurologist for a formal evaluation. Frame it to your wife not as giving up, but as getting her mother the right help so you can give her the best quality of life possible.
Start educating yourselves. Alzheimers.gov has excellent resources for families, as does the Alzheimer’s Foundation of America and AARP’s Dementia Resource Guide.

One more thing worth saying gently: Your neighbors were remarkably understanding. That grace has a limit.

—Ilyce

Classic Prudie

My fiancée and I are getting married this summer and have a wedding budget of $30,000 for 175 guests, which is below average for our state (and we live in the largest metropolitan area). My father is a stingy multimillionaire who has refused to provide more than $7,500 because he thinks, on principle, that each parent should pay for a quarter of the wedding.

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