Strong-hearted

Ye had better," said Mrs. Saddletree. "I will be wanted ower yonder," indicating the Tolbooth with her hand, "and I maun leave him now, or I will never be able to leave him.I fearna for his life—I ken how strong-hearted he is—I ken it," she said, laying her hand on her bosom, "by my ain heart at this minute."

“You're a strong-hearted girl to have taken all that without fainting.”