If cradle cap is persistent and the 'oldies but goodies' treatments of a bicarb and water paste or olive oil don't work, head for Lush and pick up a block of their Soak'n'float. It smells strong because of the herbs in it, but it is VERY safe to use on baby skin (my daughter can't use commercial soaps and shampoos due to allergies, but she is fine with this) and it cures the problem with only a couple of applications.

Kerrie