At the moment i am almost 22 weeks pregnant and my sister found out a couple of weeks ago that she is also pregnant. IM delighted! She already has a little boy who is a year a half, however, she had 3 miscarriages before him, and hey found out she had a blood disorder and had the inject herself very day during her successful pregnancy. Because of her history, she was sent for an early scan today and they saw twins!! However one twin is measuring 7+1 but the only s only 6+1 so a it of a difference. Also the smaller twin is located behind the other, making it difficult to locate a heartbeat. She has to go back in 10days and has been warned that the smaller one may no longer be there, however it could have caught up. Does anyone have any experience of this? Twin r not in of family so we feel a little clueless!