Removing character transfers on clothes

[georgetteheyersbonnet]

A friend has passed on some pyjamas for my DD - the underlying fabric is great and good quality so I'd like to use them, but a lot of the character transfers on the fabric are worn and broken and coming off in parts.

Any tips for removing them completely? At the moment the transfers aren't coming off easily and they are broken up in lots of little bits so I can't peel them. Would ironing help? Any other suggestions?