Text popping up even when phone is sleeping

[espresso1967]

Ok my wife asked me to come on here and find out how to set her text back to normal. she said that she done something that now pops up all her text even when the phone is on sleep. She doesn't want her text to just pop up for anyone that might have her phone looking at it see her business. What settings does she need to go to to revert back to non pop up text?

Any help is greatly appreciated.