It's a Surprise

A three-year-old was helping wrap a present for her father. While
they were wrapping, her mother kept reminding her daughter about
keeping the present a secret so it would be a surprise. After the
present was wrapped, she proudly put it on the table.

When her father came home he saw the present immediately. He asked
the little girl, "What is it?"

"I can't tell." she said proudly, with a look towards mom. "It's a surprise."

"Can I shake it and guess what's inside?" asked Dad.

"No," she replied, "shirts don't rattle."