Once upon a time, there was a little girl named Maria. Maria liked to go into the forest to play.

One day, Maria went down a trail she had never been on before. "This wasn't here before," she thought to herself.

She kept walking until she saw some glimmering near the trees. She went to see what it was...

The next thing she knew, she sees a smiling bone. "Hi my name is Patella," the bone said. "Would you like to be my friend?" 

"Yes," responded Maria. 

"Okay, let's play together!" Patella said. "But I can't stay until you learn about me. The more you know about me, the longer I can stay and play."

"I know that you're a bone in the appendicular skeleton because you're a part of the lower limbs," Maria said.

"Correct! I am triangular shaped sesamoid bone, and actually the largest sesamoid bone in your body," said Patella.

"Cool, I never knew that! What are you made up of?" Maria asked.

"Since sesamoid bones are a type of short bone, I am mainly composed of spongy bone which makes me dense!"