I got pregnant after sleeping with my BF and his dad

<img src="http://images.fotosearch.com/bigcomps/BDX/BDX282/bxp48578.jpg" /> I have a good news and bad news The good news is that I'm pregnant, but the bad news is that i don't know who is the father of my future baby. This all happened few months back when I slept with my boyfriend as we used to do often, but the problem is that I slept with his father too, for a couple of times .....  in almost the same time period. a friend of mine told me to ask them for a DNA test, so either one of them would be the father, but the problem with this method is that it won't show any difference between a father and his son, that's what I heared. not only that, If I told them that I'm pregnant, what would be their reaction? they both love me very much, and don't know that I was fucking around with the other p.s.  No matter what happen, The baby is mine, and I'm going to keep it