If your under 3 is tall enough to go on the rides, they will need either a ride wristband or ride tickets. These can be purchased in the Adventure Theme Park, on the day of your visit.
We have 'Little Penguin' wristbands for £7.00 for children who are 0.8m-1.0m in height, which allow access to 8 rides - 3 of which will need 1:2 adult accompaniment.