why arent short texts showing in my threads

[Android Central Question]

I have an HTC one thru att. Sometimes i hear the alert for a text but when i look at it there are no texts. I think i have narrowed it down to short texts like lol or something else real short doesnt show up. For example, i just sent my wife a text asking her for an eta. My phone beeped but there was nothing there. I asked her again and same thing happened. Then i asked her to send again only a longer response and that went thru. Her first two answers were "5". So possibly just texts that arent long enough arent showing up? I dont know.