Emergency call buttons

My mother, rather feisty, lives with us in an annex.
Last week I mentioned her footwear as not being very suitable. She responded by telling me that she’d had no problem with her sliders and found them very comfortable. Even with her toes over the edge?
Last evening after sorting her out, picking up broken crockery and mopping up blood I think she now agrees with me!
Luckily she didn’t do any serious damage.
Another thing she has been resisting is an alarm. It’s a long way from our bedroom to hers and I believe she may now be in the frame of mind to accept one.
We don’t need an outside agency, just one that alerts us at night or during the day when we maybe outside.
If there are any recommendations I would be grateful.