It will progress so make plans knowing that.
My Mum died 3 years ago. I inherited Dad who was never the most confident of people, but a lovely and patient person.
I would care for him with a daily phone call, then video calls because we are 100 miles away, then he started having falls, then he was diagnosed with mixed dementia (vascular and alz), then he was getting confused during video calls, then he fell again, then the hospital started rolling their eyes at me!
We knew we needed a plan. And his only options were carers calling in (didn't want random people calling in, a care home (didn't want that) or to try and move to live with us and see how it went (his choice and one we were prepared to offer).
He has been with us a year now. I cannot deny my world has shrunk rather. He needs more and more help as the condition progresses. He's had a bad week (behaviour and mood changes) and I almost thought we were close to the end of the care we could offer but he has improved a bit so maybe not.
The plan is to care for him 24/7 and have a months respite in a care home at least one a year (he's had one month earlier this year). Sell his house and make his money buy as many care home years as possible as we know there will be a limit to when we have to call it a day. We've had what I call "fecal incidents" and these behavior changes and I believe if they become more sustained then we will have to hold our hands up and say this is beyond our ability.
So, what I'm trying to say is, be aware this is the start of a progession of her decline. Look at the whole situation and discuss a plan with your siblings. Otherwise "just helping out" will simply become more and more burdensome.
Good luck. Its hard. Beyond hard at times.