Annie208,
I'd sharpen my pencil for Forteo for her.
She might take Prolia and not have any side effects. Some have such debilitating effects that they go to bed suffering and never resume walking. She is more likely just to have joint pain. Prolia depresses the immune system. She would be more susceptible to passing flues and viruses, but also pneumonia. If she were to experience side effects, she'd be stuck for six plus months. Of course, she may not have side effects.
Forteo build bones they way our bodies naturally build bone. It is strong, integrated, flexible bone, resilient under the pressures of the minor falls a person is likely to experience.
Some experience side effects, but the drug leaves your system usually within 4 hours. So you can just stop taking it. I'd risk any of the other meds before risking Prolia. It might make her miserable.