A pioneering procedure using high-powered sound waves has the potential to treat identical twins affected by a serious but rare condition during early pregnancy, a study has found. Blood flow between babies with twin-to-twin transfusion syndrome (TTTS) is uneven, leaving one baby dangerously small and the other too large, putting their survival at risk. Following the world-first treatment, Nancy and Margo were born healthy and, now aged four, will soon start school. Their mum Brioney said: "Every day I still count my blessings." Tap the link in BBCNews's bio to find out how the treatment works. #TTTS #Pregnancy #BBCNews