Cindy that cant be right!! We were there in Dec my little guy was going on 4 years old and was 42". He rode ET . I found this for you on universals website hope it helps.
At each UNIVERSAL Orlando attraction location, signs post specific height requirements and warnings for certain medical conditions. Children under 48" (1.22 meters) must be accompanied by an adult at all times.
All shows accommodate guests with disabilities. The outdoor-stage shows have reserved areas clearly marked by signs displaying the International Symbol of Accessibility. For more information, please click herefor our online Guide for Guests with Disabilities.
At Universal Studios®, children must be able to sit upright unassisted on all rides. Guests under 40" (1.02 meters) tall may not experience Back To The Future The Ride® and must use the stationary seating at The Funtastic World of Hanna-BarberaTM.
Due to the nature of the attractions, expectant mothers are requested to avoid riding Back To the Future The Ride®, Earthquake® The Big One, Kongfrontation®, Jaws® and use the stationary seating in The Funtastic Word of Hanna-BarberaTM and Terminator 2:3-D Battle Across TimeTM
At Islands of AdventureSM children must be able to ride upright unassisted on all rides. Persons under 54" (1.37 meters) may not ride Dueling DragonsSM or The Incredible Hulk-CoasterSM , those under 52" (1.32 meters) may not ride Doctor Doom's Fearfall, those under 42" (1.07 meters) may not ride Popeye and Bluto's Bilge-Rat Barges, those under 44" (1.12 meters) may not ride Dudley Do-Right's Ripsaw Falls, those under 42" (1.07 meters) may not ride Jurassic Park River AdventureSM and those under 40" (1.02 meters) may not ride Amazing Adventures of Spider-ManSM. Guests must be at least 36" to ride Woody Woodpeckers Nuthouse Coaster and 42" to ride Men In Black: Alien Attack. Guests must be at least 36" to ride the Flying Unicorn coaster. Pteranadon Flyers is designed for children 36" to 56" tall. Adults over 56" must be accompanied by a child meeting this requirement.
Looks like at Universal (Not IOA) there isnt anything he cant ride providing you ride with him. Have Fun!!