This is a lovely improvisation designed to help your child to engage in imaginative play.
Take your child on an imaginary journey through a forest, where you come across a Dream Tree. Together talk about how the tree looks - it often changes size, colour and shape, so it could be different every time you come across it.
As you get close to the tree you both get sleepy, fall asleep and have wonderful dreams. Take it in turns with your child to talk about the dreams you've had - you can then play a game based on one of the dreams if you like, or venture further into the forest and see if you can find another Dream Tree.