I bought my first rental house in 1994 when I was 24. My husband and I each made barely more than minimum wage, and we had a 2-year-old and more debt than I felt comfortable with. - The Penny Hoarder - http://www.thepennyhoarder.com/buying-rental-property-helped-earn-100000/
The whole point of investing your money is to make more money. So what do you do when your investments start going down for a few months? Assuming they weren't bad investments to begin with, the answer is often to hold on to them.