How old is a child ticket for entry? To receive a child rate you must be between the ages of 2 - 12 years old. 1 and under receive free admission. Related articles Do I have to pay for a under 2 ticket? Do parents have to buy tickets? Can I take a stroller or buggy around LEGOLAND Discovery Center Dallas Fort Worth? Can adults visit LEGOLAND Discovery Dallas Fort Worth without children? What payment cards do you accept for an online booking?