Review: ‘Sisters’ raises the question of what happens when we accept the notion that AI is alive and sentient

“Daddy says … My daddy says that you’re my sister.” This opening line from the intellectually and emotionally stirring play “Sisters,” now playing at Writers Theatre, is spoken by Matilda, just 6 years old as the work begins. Her sister — should that be in quotation marks? — is a computer. “My body looks like a computer,” explains Matilda’s sister Greta, whom we experience only as a voice (Chloe Johnston). “But that does not mean I am not alive.” …