Too late for manners

My 4-year-old daughter was licking her toast from her plate this morning. I told her she wasn't a pig and to eat it correctly. This seemed to amuse her so she continued after I asked her to stop. We recently bought "Richard Scarry's Please And Thank You" book for her and she enjoys it, so I told her that Lowly would not approve of her actions.
"Why?" she asked.
"Because licking your toast is having bad manners," I told her. "It's showing bad manners to lick your toast and Lowly knows that. He doesn't like bad manners so he would not like to see you lick your toast."
"But he's not real, Mommy. He's only pretend."
"Well, the man who wrote the book about Lowly is real and he would not like to see you have bad manners and lick your toast," I replied.
"Well I think he took a long time to write the book," she said.
"What do you mean?"
"He took too long to write the book and so it's too late."
Near exasperation with her, I ask what is too late.
"It's too late for me to learn good manners."
My husband, who had been listening to the conversation while working on the computer, told her it was never too late to learn good manners.
She just grinned at us.