If your mother lives there with you, I suggest your using a motion detector with a remote alarm, so you can hear when her feet hit the floor. Others will suggest pads on the bed or on the floor. The ones on the bed are felt and can prove annoying. The ones on the floor can themselves produce tripping and falling. The motion detector can be situated in an unobtrusive way, and it will reliably signal to you in another room that she's up and about.
Another thing we used when my mother was ambulatory was - and is still - a video/audio monitor. The camera eye is on her at all times; it swivels; and it allows me to see when the room is pitch dark what she is doing. I love it.
Finally, if she is falling when you are not there, do you know if she is having seizures and then falling, or just falling from lack of stability/balance. When my mother was first diagnosed, and even since, she had seizures, which indicated that her medicine needed to be changed. A walker won't help if she is having seizures.
I disagree with nitram on the walker idea. My mother LOVED her four-wheeled walker, a rollator walker, which we called her "hot rod." She refused to use the traditional style walker, as it signaled old age.
I will post links if you want to know the equipment we used/use.