"Thirty-six," he said, looking up at his mother and father. "That's two less than last year."
"Darling, you haven't counted Auntie Marge's present, see, it's here under this big one from Mommy and Daddy."
"All right, thirty-seven then," said Dudley, going red in the face.
Harry, who could see a huge Dudley tantrum coming on, began wolfing down his bacon as fast as possible in case Dudley turned the table over.
Aunt Petunia obviously scented danger, too, because she said quickly, "And we'll buy you another two presents while we're out today. How's that, popkin? Two more presents. Is that all right''
Dudley thought for a moment. It looked like hard work. Finally he said slowly, "So I'll have thirty ... thirty..."
"Thirty-nine, sweetums," said Aunt Petunia.
"Oh." Dudley sat down heavily and grabbed the nearest parcel. "All right then."

Harry Potter and the Philosopher's Stone - Chapter 2 : The Vanishing Glass
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