Does a tool or device exist that would allow my disable wife to open heavy double hung windows?

Skip, did you have a chance to check out the information I provided in my answer to your first question on this topic?

FreqFlyer provided the URL so you can refer back to it to see our responses in that first post.

I did take the time to do some research for you; I hope it was helpful or that if you haven't checked it out, you'll do so. There was one device that I thought might be workable.

if you have the money for new windows, buy them. Or, at the very least, have wifey pick four she likes to open and replace those. Before you do that, though, make sure she can open the NEW ones. Even in the best of health, an 80-year-old women's upper body strength leaves much to be desired.

Could be that the tool or device she needs to open the windows of her choice is you. ;)

Skip, I can understand your wife wanting to open the windows to get fresh air, I do the same thing.... but I really believe the only answer is to get new windows. I doubt there is any device that would be easy enough for your wife to use to open the windows.

https://www.agingcare.com/questions/devices-to-lift-and-open-heavy-windows-182620.htm