It's not (just) about what she heard at age two or three, hair pulling, including eyelashes, is a sign of anxiety, like nail biting.
I was a nail biter, though in my case, I only bit my nails in times of stress.
So yes, at ten, she is pre-pubescent, she is maturing rapidly and it is a stressful time. So maybe, like me, that's all it is and she will again grow out of it.
My own daughter, however, has a more severe anxiety disorder and is now in therapy (having to do with eating, germs and getting sick.)
Try not to make TOO big a deal out of it unless she is literally pulling all of her lashes out. Then yes, by all means, get some professional help!