 Pediatric patients with chronic liver disease may have Minimal Hepatic EncephalopathyMHEwhich can cause changes in behavior,intelligence and neurological function.By utilizing cognitive and developmental testing we will determine if patients have MHE. If so, we will trial 3 months of blinded placebo or Lactulose treatment followed by a washout period with no treatment. At this time patients are re-tested and then begin another three month period switching to the opposite treatment of first 3 months.Final cognitivedevelopmental testing will determine if Lactulose treatment has any effect on MHE. 