ALF begins its fourth and final season with a major addition to the cast--or more precisely, two major additions. Infant twins Charles Nickerson and J.R. Nickerson share the role of baby Eric, newest member of the Tanner family. In his efforts to adjust to this new "life-form", the Tanners' resident space alien ALF begs for the opportunity to serve as babysitter while the family is out. Dutifully, ALF changes diapers and burps the kid--and inevitably, he misplaces little Eric! ~ Hal Erickson, All Movie Guide