i was going to suggest a medium motherease airflow. my 19 mo old is in mediums for everything but the medium airflows seem to fit smaller than other covers. she is a little over 20 lbs and about 31 in tall or so.
for your twins you could do a m/l airflow or a straight med in bummis, or prowrap. for the babe a medium airflow should fit, or small in bummis or prowrap.
for your twins you could do a m/l airflow or a straight med in bummis, or prowrap. for the babe a medium airflow should fit, or small in bummis or prowrap.