Toyota Repair: Battery wont start the car

Question
I have had my battery die on three occasions in the last two weeks. The battery checks out good. Here is the scenario that causes the death.
My wife starts Highlander 2006 and drives to work. On her lunch break she sits in the car, turns the key to "on", rolls the window down, turns car off, takes the key out, eats lunch (:30 min), turns the key back to "on", rolls window up, turns key off, takes key out and goes back inside.
When she gets back in car to come home the battery is dead. It gives a dying attempt to turn over, but doesn't. Then nothing, no click, nothing.
The second time this happened it did click, but not the first or the third time. The car easily takes a jump from my truck every time and starts again on its own after 3 minutes of driving.

We have both driven the car multiple times during these two weeks without incident. It only happens after the lunch procedure.
I know I should just tell her not to eat lunch and that would probably fix it, but I'd like to figure this out.

Answer
Hello, let's suppose for a moment that she listens to the radio for 30 minutes, with a good battery this should not happen so I going to rule that out, a weak battery or not fully charged battery can cause this to happen, it's obviously a voltage supply problem since it starts with a jump start, I don't know how the battery was checked, if it was only checked with a voltmeter and not tested under a load then I would recommend that you have the battery load tested using the proper testing equipment, most auto parts stores will check the charging system/battery at no charge.