What makes a cartoon character appealing

To be able to design a successful 3D character it is important to discover what makes the characters on the market today appealing to today's audience. As such several children were asked who their favourite cartoon character was and why. So far amongst those aged 10-14, Phineas and Ferb was the most popular cartoon, with Ferb being liked due to his green hair and Isabella because of her catchphrase "wot cha doin'". Not enough data has been returned to ascertain which characters appeal to the younger audience.