An infant can regard his parent's face, follow to midline, lift his head from the examining table, smile spontaneously, and respond to a bell. He does not yet regard his own hand, follow past midline, nor lift his head to a 45deg angle off the examining table. Which of the following is the most likely age of the infant?

At one month, infants typically regard face, follow items to the midline, begin to vocalize, respond to a bell, and lift their head from the examining table. An 8-week-old child normally should be able to smile and coo when smiled at or talked to. Not until about 3 months of age would an infant be expected to follow a moving toy from side to side and also in the vertical plane.