Rhyming

We need to work on the concept of rhyming.  In the car today:

"This old man, he played five, he played knick knack on my door..."
Then-
"This old man, he played five, he played knick knack on my knee..."
Then-
"he played five, he played knick knack on my shoe..."
She did pause once, and I thought she had it, but it went like this-
"he played five (it's always five), he played knick knack .... on my........ (deep breath).... trees"
So close!!