My Laptop has a screen crack and I dont know why?

Hi...my daughter picked up our laptop and it appears to have a black spot underneath the screen and a few thread type cracks. The weird thing is no one used it or dropped it previously to her picking it up since yesterday..is there any other reason this could have happened besides it being dropped or stepped on? Thanks! Cressida

The same thing has happened to my 2 month old H.P. laptop. I closed the lid one night just to prevent dust getting on it while I went and got a cup of tea, came back and opened it and it had a black spot in top right hand corner with what looked like panel damage across the top and down centre of the computer. H.P are accusing us of physical damage to the screen and are not going to cover it under warranty, yet we did not do anything to it. What do you think?