Vaseline really does work. Years ago, when he was a little boy, my Uncle cut his eyelashes down to the skin. The doctor had my Grandmother use Vaseline on them twice a day. My Mother and Aunts and Grandmother (and me) all had or have very sparse short eyelashes. My Uncles lashes, even at 60, are do die for - all thanks to the Vaseline.
I'd use it, but I can't stand the feel of it on my lashes.