You are becoming a woman! Women have big hips. Your friends will soon start to get bigger hips too. Of course everybody is different and you may always have bigger hips than other girls (and smaller hips than other girls). Remember that Strong is the new Skinny and also remember that you are only 12 and still have a lot of developing to do. Unfortunately during puberty, some parts of you can decide to grow before others but with time, you will 'even out'. To help with your flat bottom, you can try some bottom muscle strengthening exercises like squats and lunges. Then not only will you have a nice round bottom but it will be strong Above all, be confident and comfortable in your skin. You are young, healthy and beautiful!