Turn off long press edit of home screen?

My mother is in her 90's and we have set up her iPhone to be easy to use by replacing most of the app icons with large buttons that execute shortcuts so she can call or message her relatives easily. The trouble is that, whenever I visit her, she has managed to lose the layout or even delete some of the buttons altogether. I think this is because she is inadvertently doing long presses rather than tapping. She must then accidentally edit her home screen. Is there any way to turn off long press editing or change the responsiveness of the touch screen to help someone with less flexibility in their fingers?