Dr. Curtis 

On a small farm outside of town, lived a boy named Curtis. Curtis was seven years old and he wanted to become an animal doctor someday. He always loved animals and helped take care of them on his family's farm. 

Curtis liked to feed the horses, chickens, pigs, dogs, and the cat. He also like to help take care of them when they got hurt or sick. Once, Curtis stayed in the barn all night, helping his father with a sick pony. The animal doctor was there too, and Curtis watched everything that he did. The doctor had to keep giving Bonnie the pony some medicine. And he kept checking her eyes and mouth. 

When the pony got better, the animal doctor went home. But Curtis and his father stayed in the barn with the pony until it became light outside. Curtis had gone to sleep, so his father carried him to their house and put him to bed. 

Curtis was so tired that even the smell of bacon from the kitchen didn't wake him up. Later, his father came and woke him. "Bonnie is going to be alright," he said to Curtis. 

"Really?" the boy said as he rubbed his eyes, "I got to go check on her." 

"That can wait. Right now you need to eat something. I saved you some bacon, Mr. sleepy head," his father said as he smiled at Curtis. 

Curtis washed, dressed, and ate as fast as he could and then raced to the barn. He stood on a stool and looked into Bonnie's eyes and mouth. He put his head on her chest and listened to her heart. Then he checked her legs and tail. He tried to do everything the animal doctor did and more. 

Curtis saw his father standing at the door and said, "Everything looks okay, daddy. I think she can go out to the big tree with the other horses." 

"Okay, Dr. Curtis," his dad said as he patted Curtis on the back. "Let's take her outside."
What nick name did his dad give him?
"Okay, Dr. Curtis,"