My twins were born at 37+2 weeks 3 days ago. My daughter was 5lbs 2oz and my son 6lbs 1oz. They were feeding fine both taking between 30 - 40 ml of milk every 3-4 hours. My son was always taking between 40-45 ml up until today where he's only taking around 25-30 every 4 hours. We were using the pre made bottles while in the hospital and now at home we are using tommee tippee slow flow. My daughter seems to be fine and has started to take more milk but my son seems to be taking less and less which is worrying me as he's always fed no problem. Is this common or should I be concerned?