The only List that I am aware of that has child or infant in brackets after the names of Children and Infants in the White Star List of May 1912 as published in A Night to Remember. It is not however completely accurate. Otherwise; you may find Lists which gives ages. On such Lists those under the age of 12 are Children [12 and above counted as Adults]; and those aged only in months Infants. On other Lists you can generally identify male children because they have Master in front of their name; but on those Lists you cannot easily identify female children.