Not to be an ***, but...
Does she know first aid?
Sign her up for a class (eg, red cross)
and she can make a road-side-safety kit as part of her training.
Then speparate out the mechanizal stuff from the first aid stuff.
It's more important to understand how to think in an emergency that to have lots of **** in the trunk.
Now, a couple key things:
1) Communication device (and somebody to call)
2) Bottled water, age/diet approriate food (to help think straight)
3) Gloves, Socks, Hat, etc for extremities (sitting still --> cold)
4) Light-source (LED+lithium bbatteries)
5) Plan (B) for 1, 2, 3 so there is some redundancy
5.2) Actual firts Aid Kit (see: adventure medical kits)
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6) Stuff for a good samaritain to help
6a) Ducktape, Pliers, tools, etc
6b) Fluids, spare fuses, jumpers, etc
6c) Work gloves (nitrile and cold weather / mechanix or what not)
6d) Rags/paper towels/dishsoap/clorox wipes/etc
6e) One nice thing is a mat or something to throw on the ground.
(kneeling on wet ground in the rain with wind etc)
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I would say those are roughly in order of priority.
Lastly, even if you have all this gear, you need some knowledge.
Like....don't open the radiator cap when the engine is hot.
Of course, how long does it take to wait to cool the motor?
By then the car should be towed. or just dial 911 if the outlook is negative.
Hope this helps.
