iPad Clock app not working

Our son's iPad Clock app has stopped working. He is an adult with Autism and he relies on the Clock app's Timer function for many things. It has been frustrating for him but we have, so far, managed to redirect him with another timer.

What is happening: we tap on the Clock icon, we set a timer, we hit start and the app closes.

The problem had happened in recent weeks but seemed to be resolved by an update. It has now returned.

As far as problems go, to us, it's an inconvenience, but to our son, it's harder to manage. He is on the more severe end of the spectrum and these things are difficult to explain as he has other underlying issues. We will, of course, buy him a new iPad in the coming months (it takes some juggling), but would like -if possible- some suggestions as to what might be the problem and how to -maybe- fix it.

I appreciate that our son is the one who needs to adjust to these difficulties, but as older parents, we do appreciate any help to see our way (if there is one) through this. Of course, he needs to learn to cope, but we are his only caretakers and we want to find ways to make everyone's life at home a little easier to manage until we can afford to replace this piece of equipment.

Suggestions are sincerely appreciated. If it must be replaced ASAP, we'll figure it out, but if there's a way to fix it for a good interval of time, that would be awesome. Any thoughts?