Advice on PIP & ESA please

Hi,
I would like advice please for a family member who is in receipt of PIP high care with mobility and ESA support group ,due to severe illness and being bed ridden. They would like to attempt to publish poems they wrote some years ago, before becoming ill but worried this would affect their benefit, which was very difficult to get. They are not very likley to make any money but would like to publish their work. Thank you so much.