cradle cap at 1 month

Isabel • Anything can happen

my baby was born with the very clear skin no cradle cap just perfect...one month later I can see she has started to develop a cradle cap? and im saying because she didnt hVe it at all before I examined her like any mother in love with their baby would but anyone know why and what do I use, should I use coconut oil on herscalp?? help please &thank you