Finding the tiniest resident of a bustling animal shelter in Southern California was difficult. The 2-month-old Chihuahua was cowering at the very back of the very last kennel.

Almost as if he didn't want to be found.

But there was something about the Chihuahua, who would come to be called Little Crow, that stood out to Amy Klein, who works with the animal rescue group Marley's Mutts.

"His head was enormous," she tells us.

Not only that, he only seemed to walk only in wobbly circles.

They were the telltale signs that Little Crow suffered from hydrocephalus, which is water on the brain.

But nothing else about Little Crow added up. He was supposedly found on the streets as a stray.

"I can't imagine what that means, given his size, but a lot of times people will turn in animals and say they found them as strays, as opposed to telling the truth," Klein says. "It costs money to surrender one of your pets."

Then there was the fact that Little Crow should be blind due to the fluids weighing on his central vision center. But he not only sees his world, but he also pounces on it.

And he's supposed to be able to use only 20 percent of his brain. Yet he listens to commands and already knows how to sit.

Did we mention that his brain would collapse if the fluids were drained? Or that he shouldn't be around at all? He was scheduled to be put down just a few days after Klein found him.

Don't tell any of that to Little Crow.

Since he's been pulled from the shelter and taken in by a loving foster family, he thinks he's just a puppy.

He loves stuffed toys.

And looking at himself in the mirror.

It's hard to blame him.

Because the fluids in his brain couldn't be drained, Little Crow was put on medication, hoping the swelling would ease.

And it did.

"His brain swelling has gone down considerably," Klein notes. "To the point of his eyes are no longer bulging on the sides of his skull."

Now, when he visits the clinic for a checkup, veterinarians gather around him because this is what a medical miracle looks like.

"The doctors are so flabbergasted that when he was brought in for his meeting with the neurologist, other veterinarians at the hospital came running to meet him," Klein explains.

Little Crow, true to the great Native American leader he was named after, is a warrior.

He may not live the most extended life. He may someday develop seizures or crippling headaches.

But if Little Crow has taught us anything, it's that no one should bet against a miracle. And that even impossible dogs have a heart full of possibilities.

Maybe the biggest miracle is that Little Crow is available for adoption in the Bakersfield, California, area. Few expected he would be well enough to find himself in need of a happily ever after.