"R-7," he called. "R-7."
"Here," came the robot's voice through the audio. "Is that you, father?"
"Father?" Hen ejaculated. He heard Sofi giggle. "Where did you get that idea?"
"Didn't you make us, father?"
"Yes," he admitted. Sofi was laughing out loud. "But you didn't think of that yourself."
"The girl told us, father," said the robot.
Hen ground his teeth. That, of course, was Sofi's idea of a joke. "Where have you been?" he asked.
"Prospecting."
"Prospecting for what?"
"Radium, father."