Children's Entry
Children 24 months and older must have a ticket in order to gain entrance to the AT&T Center. Children under 24 months of age may enter without a ticket but must sit on their parent’s or guardian’s lap. PLEASE NOTE: Some events will require all attendees regardless of age to present a ticket for entry into the AT&T Center. Please check the event’s ticket policies at the time of purchase.
http://www.attcenter.com/arena_info/arena_faq