The shock gesture was reportedly to help raise money for treatment, and the card had a hand drawn image of a dragon.
It read, "Leah, hope you get well soon," and was signed off with Salvador – the name he has adopted in tribute to the painter.
Bronson, who has already served 40 years of his life sentence for robbery and kidnap, spent a day creating the card after his pen pal Darren Holdcroft told him about leah's tragic accident.
This isn't the first time that Charles has reached out to the sick or injured: he has already donated pieces of artwork and a self written book to four-year-old leukaemia sufferer Frankie Allen.
Talking to the Mirror, Bronson's pal Darren commented: "Frankie's dad asked me if i could mention it to Charlie to see if he could help Leah and her family with any future fundraising so he spent a day creating this get well soon piece for her."
The wakefield prisoner who received his first sentence at the age of 19 for armed robbery and added charges for inmate attacks and hostage incidents has created around 100 'fantasy reality' art pieces and can often bring in between £400 - £1,000 at auction.
Pal Darren continues: "The amount of art he produces for sick children is unbelievable and he has helped raise thousands of pounds. Hopefully he can help raise some funds for Leah."
Words by Katie Woodward