Using the People/Families Menu select "Add New Person"
This will bring up the Person Editor, add the title, name, and other attributes as you would normally. Using the Family Link View:
From this view scroll down until the correct family record is selected (Highlighted with Blue) The following selections can be made
Unassigned: The person is not linked to a family unit
Create a new family (using last name): A New Family record is created and the person is linked to it
Selected Family (By Last Name & Address): The person is added to the selected family record
Select the appropriate family role (CHILD)
Continue filling out Phone Numbers, Birthdates, Email addresses, and other person data.
Select SAVE, this will bring up the Person View
There will be a link to the family just under the Persons Name. (See illustration above). Clicking the last name of the family will go into the "Family View" which has a table towards the bottom of family members.