Sounds like the display cable may be getting interfered with. Pinched or pulled a little loose.
If the laptop is under warranty, I would contact the manufacturer. If it isn't, then it depends on what you feel comfortable doing. If you are OK with (and she is OK with it) opening up the laptop and carefully checking the cable for the display, then you can do it yourself. If not, then I would suggest going to a local tech. Better to pay a little to get it looked at than risk damaging it.