Text Log - Why my number doesn;t show up on the text log when her Or I text eachother?

Many texting apps (e.g. iMessage) don't use SMS unless configured to, they would use data.

You wouldn't see data usage if you were on Wi-Fi.

So if the persons phone has no wifi then the texts  would show up in the data log ?

Data logs only show amount of data used, not what used it. So no, texts don’t show up in the data log. There is no way to know whether a data log entry is for a text or something else and when I say “text”, I mean a message through an alternate message service such as iMessage or WhatsApp. Regular SMS or MMS texts do not use data.

Do you have iPhones? If so, iMessages are not in the text log.

That makes total since.  We are usually in wifi.  I thought it would still leave a record of the text though because her friend still shows up on the log and she has iphone and is usually at work with the wifi.  hum.....I am going to ask her friend if she hooks up to the work wifi or not.

Thanks 

So if the persons phone has no wifi then the texts  would show up in the data log ?

Whether or not the phone has Wi-Fi is not relevant.  The question is the software mechanism by which the text is sent; you can send SMS/MMS messages using the cellular network (3G or VoLTE) or via Wi-Fi Calling.  Those will show up as texts.  If you use an application that sends the messages without using SMS/MMS (e.g. iMessage to another iPhone user), then that will use data and will not show up in the counts.