I know there are actual mascaras and products you can purchase that will help your eye lashes grow, many I have heard of are meant to be applied over night.
I have also read that castor oil helps and I read about and saw a few videos about applying vaseline to your lashes at night to help them grow. At first I didn't believe this at all but after some time of doing it I have actually noticed a big difference in how long and full my lashes look so I continue to do it. I think the point is to try and nourish your lashes over night. When I wear mascara now people often think I am wearing false lashes when all I have been doing is using vaseline before bed and my usual mascaras.