My screen on an ipad pro 9.7in has splintered around the home button

Has anybody else experienced this? The ipad was NOT dropped. It is encased in a metal keyboard cover. It has a spiral of spider fractures around the Home button and now they have extended upwards to the edges of the ipad. Everything is working fine though. We have experienced extreme heat of late and was wondering if that had anything to do with it. I'd be grateful for any feedback.