2D Cartoon Thumbnail Creation

I'm looking for a professional graphic designer who can create a 2D cartoon thumbnail for a children's story. The design needs to be bright, cheerful and appealing to a young audience. It should encapsulate the essence of an adventure-filled, comedic, yet fantastical journey that is both engaging and entertaining.

This thumnail on youtube video link 15M+ view
https://www.youtube.com/watch?v=yWC04ihdvoM

Ideal Skills and Experience:
- Graphic Design
- Cartoon Illustration
- Understanding of Child Psychology
- Experience in Creating Bright and Cheerful Designs
- Strong Portfolio of 2D Cartoon Work

Please include samples of your previous work with children-themed designs.