Emulsion painting over a mural

[jjb1333]

Hi
My son has just moved house and in one of the bedrooms the previous
occupiers have painted a giant Peter Pan Mural on what was obviously a childs bedroom
We have tried to paint over it with white emulsion but some of it keeps reappearing after the paint dries
It looks like a crayon or felt tip pen has been used
Any ideas how i can cover the wall
What paint should i use ?
What prep should i do ?
Many thanks

 

[sparkwright]

Give the wall a sanding, wipe it down with white spirit or similar and see if anything comes off.

When all dry and clean, give the wall at least one coat of white oil-based paint. Something matt like ordinary undercoat should stop the bleed-through.

Then emulsion over.