That was when Magnus realized the magnitude of the situation. It was not just a wild conclusion Isabelle had leaped to and improbably convinced everyone else of. It was not just the Lightwoods.
Alec thought that he and Magnus were keeping the baby as well.
Magnus did go and sit down then, on one of the rickety chairs with a cushion from home placed on it. He could not feel his fingers. He thought he might be in shock.
Robert Lightwood followed him.
“I couldn’t help but notice that the baby is blue,” Robert said. “Alec’s eyes are blue. And when you do the”—he made a strange and disturbing gesture, and then made the sound whoosh, whoosh—“magic, sometimes there’s a blue light.”
Magnus stared at him. “I’m failing to see your point.”
“If you made the baby for yourself and Alec, you can tell me,” said Robert. “I’m a very broad-minded man. Or—I’m trying to be. I’d like to be. I would understand.”
“If I made … the … baby … ?” Magnus repeated.
He was not certain where to start. He had imagined Robert Lightwood knew how babies were made.
“Magically,” Robert whispered.
“I am going to pretend you never said that to me,” said Magnus. “I am going to pretend we never had this conversation.”
Robert winked, as if they understood each other. Magnus was speechless.
— Born To Endless Night, Tales From The Shadowhunter Academy