Cheers!
First, when you plug in the power cord there will be an indicator light on the computer illuminated. This then tells you the power cord is NOT the problem as the light is saying it is getting wall power
On many laptops if the batter is completely discharged or defective they will not start up. Try leaving the wall plug in to the computer and remove the battery and see if it will power up. If so she needs to either try letting it charge overnight and try again. If this does not work get another one and maybe a spare as well. She can of course run in this configuration as long as she can plug in to a wall plug.
As to all of the comments on overheating if you let it be powered off for 2 hrs or so (depends on room temperature) the thermal protection in the unit will reset and it will start up. There are micro fans on the edge and or bottom of the computer, make sure they are not clogged with dust which can happen more frequently in carpeted or other high dust/lint areas. Also, get one of the new devices on the market that lifts the unit up approx 1/2 inch or so and may even have a fan, it fits under the laptop and helps keep the indie parts cool
I she has it plugged in and sees no no light on the unit then try moving the power plug gently to see if the indicator light comes on. If it does she should take it to an authorized repair location and have them check the pins on the motherboard where the connector plugs in, they may be bent and need only be straightened
I own a toshiba. The fans are a weak link on them.
Wait a half an hour. Try to boot it up.
If it boots up, and then quits after about 5-10 minutes, you’ve got a heat problem, likely the fan is out.
If it’s not charging, the problem is with the laptop jack. Toshiba is cheap with the jack and it’s really easy to have a bent/broken jack.
Grey whiskers; why would you want to hijack this ladies thread about fixing her daughters computer with an attempt to start a flame war? You are well aware Jim has asked that to stop.