Hi Jenny. If it's the softness of her voice that's an issue there are inexpensive amplifiers on Amazon that have a small microphone on a headset.
There are also free apps that convert text to voice on an iPad. I plugged in a bunch of phrases for my dad and all he had to do was hit a button. For free I thought the technology was pretty good. I'll have to search for the names and let you know.
In the end we used a dry erase board and my dad wrote messages to us.