Answer:
It's galactokinase!
Step-by-step explanation:
The baby has galactosemia, a genetic disorder in which there is an enzyme decifiency knows as galactokinase. This enzyme normally converts galactose(sugar in dairy products) into galactose - 1-phosphate. It's deficiency wcan lead to accumulation of galactose and galacticol in the blood. This can cause lethargy, failure to gain weight, yellowing of skin and abdominal bleeding!