What story doss the mother tell that inspired her son to climb the fence?

From the text:

One evening, the mother read the little boy to sleep with a fairy story from the book the wise old witch had given him at Christmas. Next day he pretended to be the Prince who braves the terrible thicket of thorns to enter the palace and kiss the Sleeping Beauty back to life: he dragged a ladder to the wall, the shining coiled tunnel was just wide enough for his little body to creep in, and with the first fixing of its razor-teeth in his knees and hands and head he screamed and struggled deeper into its tangle.