Can't I get into setup somehow and keep the receiver ON 24/7? (Or perhaps the OK button can be accessed withe the remote -- but I would prefer the rcvr ON all the time instead).
That way she just turns on the TV and all is good to go.
We have U-verse as well, and the one upstairs in the game room never gets turned off. It's always ready when the kids turn on the TV. I'm not aware of any of mine turning off without me doing it.
Additionally - for the one in the bedroom, I only turn it off and on by the remote that came with it (which I programmed to turn on/off my TV at the same time). I never touch the button on the front of the U-Verse receiver unless I need to reboot it.
Try asking her to hit the at&t button on the top left corner of the remote and then the OK button. Also, be careful that it does not say "press Ok to start Uverse on demand". If it does say that, simply change the channel and she should be good to go!