Where did that come from?

I'm not one to repeat "cute" things my daughters say. Generally they only seem cute to the parents. I'll make a one-time exception because this one was so unexpected, and I'm still not sure why she came up with the particular line in question.

Yesterday our two year old was repeating a rhyme she obviously picked up in her parent-toddler group. At the risk of violating someone's copyright, it goes:

Five little monkeys bouncing on the bed
One fell off and bumped his head
Mummy called the doctor and the doctor said
"No more monkeys bouncing on the bed"

Four little monkeys ... etc.

The problem was that she kept starting the rhyme with "Three little monkeys" and never went down to "Two". Stuck in this infinite loop she went on for well over five minutes chanting the one verse over and over again. Finally she found a way of ending it by saying:

Mummy called the doctor and the doctor said
"That's not my problem"

And that's where she stopped.

I'm still shaking my head over that one.