From: Star Trek: Enterprise
Caption: A Lorillian mother and child
Alpha Quadrant species. Lorillian children are born with the ability to breathe only methyloxide via an inhalation apparatus. This means that mother and child must deal with a difficult weaning process when the child reaches age four. Commander Trip Tucker observed a mother and child engaging in this process, and assumed the child was being suffocated. T'Pol corrected him.