I don't recall seeing children for sale at the concessions stand, but you could probably try to bring in your own from the outside... If you're inquiring as to the cost of tickets, FAQs on the Cinemark website list child ages from 1 to 11 years old. For regular showings, Child tickets are $6.75. Early Bird (first matinee showtime of the day, starting before 1PM) tickets are $6.00. Tuesdays are Discount Day, with tickets priced at $5.25. Premium charges will apply for nonstandard formats, like 3D and XD.
Check out https://www.cinemark.com/theatre-1078 for the correct information.
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