Depends on how bad the break.

Personally, I use bamboo stakes as a splint. Worked fine the couple of times I've had to do it.
I take a bamboo stake, cut it to about 4" long. Split it down the middle, so there is now 2 - 4" sticks. Place the sticks on either side of the break, use twist-ties to gently, yet firmly keep it in place. Reduce external stresses (fans, strong light...) and watch that the plant does not 'overgrow' the splint.

Good luck with her.