Mary Janowski is the only girl among the five children rescued from Triacus in And the Children Shall Lead, all of whom are under the control of the Gorgan.
Mary Janowski is one of the children of the Starnes expedition in the Original Series episode And the Children Shall Lead. Her parents die with the other adults on Triacus, yet she shows no sorrow when the Enterprise arrives and only wants to play.
Brought aboard with Tommy Starnes, Don Linden, Ray Tsing Tao and Steve O'Connel, she joins in the chant that calls up the being they know as their Friendly Angel. With the fist-pumping gesture he has taught them, the children fill the bridge crew with private terrors and take the ship towards Marcus XII.
Mary breaks down with the others when Kirk plays recordings of the children with their parents and then shows them the graves. Their tears strip the Gorgan of his power and reveal his true ugliness.