"Sagramore's horse." Qi Yan's affinity with horses isn't as dangerous of a secret as what she's just told Magnus, and in her childhood she was famous for it. So she doesn't hesitate to say, "I have the ability to communicate with horses. It is a gift I was born with."

Magnus' ability is likely different from hers, since so much of his life is unrecognizable to her. But she cannot shake her own associations with animal communication. To the Chengli, it would show that Magnus has a pure and loving heart. That is easy to believe.