How we cite our quotes:
He smoothed my back first and then my neck, talking all the while about [...] how I would grow up to be the smartest horse in the whole wide world" (1.13)
Albert admires Joey immediately, like love at first sight. Maybe it's because Albert sees a lot of himself in Joey—young but feisty, a lot of potential, and you know, really wants to kick his father in the shins.
I learned to come at his whistle, not out of obedience but because I always wanted to be with him. (2.2)
Joey admires everything about Albert, and that encourages him to follow his instructions. He tries to find characteristics he admires in other riders he's forced to work with, like Perkins, but with Albert, it's easy.
"I like your spirit, so when you're old enough, you must come and join the cavalry." (4.21)
Hey, it's not all about the horses. Captain Nicholls sees something special in Albert. It's probably his devotion to his horse, which would make him a great fit for the cavalry. Although Albert doesn't end up joining the cavalry, he does bring his aptitude for horses to the veterinary unit, becoming a valuable member of the military.