A LoRA of young Nick Wilde from Zootopia, for Illustrious. Trigger word is "cubnick". If you change his outfit it messes up his proportions so you might need to add something like "(young, chibi:0.3)" to the prompt.
This should theoretically work with whatever Illustrious mix you want to use, but in the case of these pictures I used Gehenna V2, here: https://civitai.com/models/1214846?modelVersionId=1435112