Jake - the youngest Tweenie with a yellow mohawk - stars alongside playmates friends Bella, Milo and Fizz in the show set in a nursery. 390 episodes were aired from 1999 to 2002 but it's recently been screened again.
It all seems very obvious now we know!
Do you also remember Doodles the red and yellow dog who helped care for them? Well yes that's Justin too!
Justin is quite prolific in the world of kid's TV! Credit: BBC
If you can handle any more information Justin also voiced Shaun The Sheep and Timmy from Timmy Time.