Simultaneously follows four babies around the world - from birth to first steps. The children are, respectively, in order of on-screen introduction: Ponijao, who lives with her family near Opuwo, Namibia; Bayarjargal, who resides with his family in Mongolia, near Bayanchandmani; Mari, who lives with her family in Tokyo, Japan; and Hattie, who resides with her family in the United States, in San Francisco.
