Why Am I Only 5' 6" at 15?

I Feel Doomed By This! My Guy Friends Are all Taller Than Me! Even the Younger Ones. I'm A Male and I Am Actually Interested in Modeling and To Model You Have to Be Tall ( 5' 11" at least) . My Dad is only 5' 9" So That Brings Me down even More... But My Uncles all over 6' 3"! They Are like giants but my dad had to be the short one. I Really Want to be 5' 11" or 6" but Ughh...This sucks! ): Is There ANY Hope for Me!? What Could I do To Grow more? I Sleep A LOT and I will admit I'm not Very Active But I Don't Eat Too Unhealthy.. (I eat Fruit Everyday) HELP!!! D: