The story is indeed a little difficult to believe. Still, you might try.
CHAPTER 4. TWO BAZAARS
Mother was really a great dear. She was pretty and she was loving, and most frightfully good when you were ill, and always kind, and almost always just. That is, she was just when she understood things. But of course she did not always understand things. No one understands everything, and mothers are not angels, though a good many of them come pretty near it. The children knew that mother always WANTED to do what was best for them, even if she was not clever enough to know exactly what was the best. That was why all of them, but much more particularly Anthea, felt rather uncomfortable at keeping the great secret from her of the wishing carpet and the Phoenix. And Anthea, whose inside mind was made so that she was able to be much more uncomfortable than the others, had decided that she MUST tell her mother the truth, however little likely it was that her mother would believe it.
‘Then I shall have done what’s right,’ said she to the Phoenix; ‘and if she doesn’t believe me it won’t be my fault—will it?’
‘Not in the least,’ said the golden bird. ‘And she won’t, so you’re quite safe.’
Anthea chose a time when she was doing her home-lessons—they were Algebra and Latin, German, English, and Euclid—and she asked her mother whether she might come and do them in the drawing-room—‘so as to be quiet,’ she said to her mother; and to herself she said, ‘And that’s not the real reason. I hope I shan’t grow up a LIAR.’
Mother said, ‘Of course, dearie,’ and Anthea started swimming through a sea of x’s and y’s and z’s. Mother was sitting at the mahogany bureau writing letters.
‘Mother dear,’ said Anthea.
‘Yes, love-a-duck,’ said mother.