"Indeed he is, Mrs. Allen," said Mrs. Thorpe, smiling complacently; "I must say it, though I am his mother, that there is not a more agreeable young man in the world."
This in applicable answer might have been too much for the comprehension of many; but it did not puzzle Mrs. Allen, for after only a moment's consideration, she said, in a whisper to Catherine, "I dare say she thought I was speaking of her son." (8.33-34)
Mrs. Thorpe seems oblivious to the actual nature's of her children, and she also seems to read a compliment to them into anything anyone says. Mrs. Allen was speaking of Mr. Tilney, but Mrs. Thorpe "complacently," or smugly, assumed Mrs. Allen was speaking of John.