Now that we've heard Kentucky Derby favorite American Pharoah's "baby story," let's turn to the tales of his rivals as youngsters. 

International Star earned the nickname "Captain Underpants" for his hijinks. 

Bred by Katharine M. Voss and Robert T. Manfuso in New York, International Star moved to their Chanceland Farm near West Friendship, Maryland, as a three-month old. He remained there until he was sold for $85,000 at the Fasig-Tipton Midlantic Fall Yearlings Sale in Timonium. 

A.J. Hesketh-Tutton, broodmare manager at Chanceland, shared her memories of his playful antics. 

International Star considered halters as "toys," as though "the only reason we put one on him was so that he could take it off as soon as possible and fling it around."

He didn't do this trick just on his own halter either, but would "go and take one off one of the other colts, and the game began again. 

"We used to laugh at him every morning, 'running around nude again?'"

And his handlers would have a task to track down just where he pitched the halter this time.

International Star had a few other favorite "naughties" -- "grabbing the end of the shank to chew it...taking your brushes out of the box while he was being brushed...slamming his feed tub up and down when he was done eating.

"He constantly tested the limits, though not in a nasty way," Hesketh-Tutton added. "If you told him he couldn't do something, he would keep very casually and very sneakily trying it."

Ironically, for all of his fun with halters, shanks, brushes, and feed tubs, he "never touched" the actual toys in his stall.

The spirited lad also had an eye for the fillies -- and the mares. He refused to be tied to the back of his stall during grooming, as all the other yearlings did, because he couldn't take his eyes off the fillies who were stabled on the row across from him.

"He had to be facing those fillies," Hesketh-Tutton recalled. "We tried everything, but he would only be brushed if he could see his 'girls.'

"And not only girls his age either! We had to switch the field he was in because he would run the fence line like a mad thing if he could see the broodmares, or the fillies, or even the fillies across the road at the other barn! 

"We ended up having to put him in a field with the teaser between him and the mares, and even then he would go and posture at the teaser to show what a little stud he was.

"We used to tell him all the time, 'if you want those mares, you are going to have to prove yourself first boy!"

Although Danzig Moon is currently billed as "racing's bad boy," thanks to a Twitter photo of the bite he inflicted on his groom's arm, that's not the Danzig Moon that Tim Beeson of Windhaven Farm remembers.

"He was just a nice foal from the very beginning," said Beeson, who manages Windhaven's division in Lexington, Kentucky. "He had a lot of class and presence about him.

"But he was not mean. I know he's getting a little bad rap for biting his groom, but I think that's just being a colt.

"He was always fun to be around, an easy horse to prep and raise.

"I'm just really happy for Mr. (William) Graham who bred him, that he can get some recognition for breeding a nice horse."

Danzig Moon was foaled at Graham's Windhaven division in Ontario, but spent only a couple of weeks there before shipping with his dam to Kentucky. Graham's mares are brought back so that they can be bred to Kentucky stallions that breeding season. Danzig Moon was sold for $160,000 as a Keeneland September yearling. 

Mubtaahij was also on the move as a baby. Bred by Dunmore Stud, he was foaled in Ireland because his dam was due to visit an Irish stallion, Acclamation. When Mubtaahij was two months old, he and his dam returned to her home in France -- at the Garçon family's Haras de l'Hotellerie. 

"He is one of our first crop that we raised at our new stud, Haras de l'Hotellerie," Guillaume Garçon said.  

"He was very quiet and friendly foal. You could do anything with him, he loved to play with you, bit you and always looking after you. He never had any problem, no medication or bandage."

But even the affable and carefree Mubtaahij made his dam, Pennegale, upset once. 

"I was looking at mares and foals in the paddock and Pennegale was running with her foal, but after few minutes the foal stopped. The mare was still running, and he went to drink milk from another mare.

"She showed that she wasn't happy, but Mubtaahij was like he is the boss. 

"I thought it was pretty funny and rare," Garçon summed up. 

Mubtaahij remained at Haras de l'Hotellerie until Arqana's August Yearling Sale at Deauville, where he sold for €450,000 (approximately $599,445). 

Stay tuned for Parts II and III