As a foster parent with Badass Brooklyn Animal Rescue, I take dogs into my home and care for them until they find their forever homes.

These dogs come from high-kill shelters in the southern U.S., and so far, I have fostered two dogs, both of whom found fantastic forever homes.

Badass Brooklyn Animal Rescue likes to give its dogs celebrity names, which makes calling them in the park even more fun. The first dog I fostered was named Ezra Klein and the second (who stole my heart) was named Ellen Page.

This is Ezra Klein, my first foster dog, a 2-year-old dachshund-chihuahua mix.

This is Ellen Page, my second foster dog, a 4-year-old "muttigree."

I'm a video producer here at Upworthy, so when I brought Ellen Page into my home, I decided to document the highs and lows of being a foster parent.

Here's what I've learned.

1. You get very little information about the dog you're welcoming into your home.

Most of the time, foster parents have no idea what we're in for — we get very little information about the dogs in advance. The anticipation of a new foster pup always makes me nervous. I call it my "pre-foster jitters."

With Ellen, all I was told was that she had "bad manners" and was "aggressive with small dogs."

Living in a community with a ton of small dogs, I was really nervous that Ellen would try to eat one for breakfast each morning. Luckily, it turned out she preferred chasing squirrels over small dogs.

Ezra Klein, day 1, checking out his new temporary home.

2. Teaching foster pups that it's OK to "go" on NYC sidewalks can be stressful.

Training a dog to be housebroken is tough, especially in NYC where grass is sparse. It's a learning process for everyone involved.

But that moment when they pee outside for the first time is pretty exhilarating. After three long days of trying to get Ellen Page to pee outside, I basically threw a party for her the first time she got it right.

Pee party for Ellen!

3. Being a doggy foster parent to a nervous puppy can be a round-the-clock job.

Pee on the carpet? Diarrhea at 4 a.m.? Constant barking and separation anxiety? Fear of being outside? These are all issues that require constant love, patience, and understanding to help resolve.

My first foster puppy, Ezra, was so fearful on walks that he would drag me down the sidewalk back to my apartment building. (He only weighed 12 pounds, but those little front legs have power — let me tell you.) I didn't know his history, but I suspected he spent most of his pre-foster life stuck in a crate and had probably had never been outside before. So I worked with Jason Cohen, a dog trainer, to help Ezra become less anxious outside ... which meant sitting outside with him for extended periods of time.

Ezra and I watched the sunset (as he tried to drag me back to my apartment). Ezra and I went on long walks (as he tried to drag me back to my apartment). Ezra and I sat and people-watched (as he tried to drag me back to my apartment).

And, eventually, Ezra realized being outside wasn't so bad.

Classic Ezra butt-wiggle

It was a relief to know that all that patience had paid off. By training Ezra to be calm outside, it was less likely that he'd be sent back to a shelter for misbehaving.

4. Walks are required frequently, even when you feel like being lazy.

You know how I mentioned it took a nervous Ellen Page three days to learn to pee outside? Well, until that joyous moment, I was walking her multiple times a day, and even occasionally in the middle of the night, just in case she suddenly figured out where she was supposed to go to the bathroom.

At one point, I found myself scraping explosive doggy diarrhea off the sidewalk in the middle of the night (which is as fun as it sounds) when I would've much rather been sleeping. But getting up to take Ellen on a 4 a.m. walk was worth it for that mess to end up outside rather than in my apartment — and to reinforce for Ellen that going to the bathroom should always happen outside.

5. The goodbye is by far the hardest part.

After I handed over Ellen's leash to her amazing new adopters, I cried. In the corner. While my boyfriend patiently patted my head.

After spending countless hours training, petting, picking up poop, loving, feeding, and playing with your foster pup, there is nothing harder than seeing that pup walk away with its new family. Leaving you. Forever.

Or you can do what I did with Ellen's adopters, and offer to dog-sit, should they ever go on vacation. I am Ellen's self-appointed cool aunt. No promises that I won't spoil her if her adopters take me up on the dog-sitting offer.

Ellen Page walking off into the sunset with her amazing adopters.

Of course, I always try to play it cool, as if I'm not crying and completely crushed, when my foster dogs walk away. But after saying a tearful goodbye to Ellen Page, another Badass Brooklyn Dog Rescue puppy, Vin Diesel, tackled me with a big doggy hug.

Vin Diesel is so intuitive. It's like he knew I needed a hug. Photo by Nikki Tappa.

Which brings me to the most rewarding part of fostering:

There, in Vin Diesel's paws, I realized that there will ALWAYS be another dog in need of a foster. Yes, I wanted to adopt Ellen Page and keep her as my own, but being a foster parent isn't about me, or about Ellen.

It's about the next dog on the kill list in a shelter down south, who needs a foster home in order to find a forever home.

As a doggy foster parent, you're saving dogs lives.

According to the ASPCA, 1.2 million dogs are euthanized each year. And every dog that gets fostered and adopted is one fewer dog on the kill list. My boyfriend and I decided that for every dog we foster, we are going to make a "paw print" (with nontoxic finger paint).

We plan on framing each paw print, so that one day, we can have a wall full of paws — all shapes and sizes. Whenever we have post-fostering blues, we'll have this wall of paw prints to remind us of the big picture.

Fostering is about saving as many dogs as possible. And that makes it all worth it.

Watch my journey with Ellen Page below: