Pushing down on the chin causes a reflex contraction in the mentalis muscle, which has exactly the opposite effect - it closes the jaw! IMO, a baby who won't open or can't open his jaw has a good reason for this behavior or inability. The solution is to find out why, NOT to force him and risk further trauma. Linda J. Smith, BSE, FACCE, IBCLC Bright Future Lactation Resource Centre Dayton, OH USA http://www.bflrc.com