hello doctor.. we had twins ,boys, on 15th Dec... t1 weight was 2.2 and t2 was 1.8 at birth. t2 dropped to 1.68 at three time of discharge on 21st. now t2 is at 1.7 only and is not gaining much weight.. we give him preNaN. 7 to 8 tubes a day of about 30ml each time.. should I continue and when can I expect his weight and growth to be on par for his age