Over the past decade, Hannah René Shaw has become a prominent educator on and advocate for kittens nationally and globally. She’s known as the “Kitten Lady,” and her 1.2 million Instagram followers look to her for advice on things like what to do if you find a stray cat, or how to get a baby kitten to eat.

But they also follow her for the barrage of high-quality kitten photos featured on her account, some of them shot by Andrew Jared Marttila, who is known as the “Cat Photographer.” The love in the photographs is palpable — after all, this is a story of how the kitten lady and the cat photographer fell in love.

Back in 2016, Ms. Shaw, who has a bachelor’s degree in psychology from George Mason University, wasn’t looking for a partner. “I was 28, and I was very much not interested in getting into a committed relationship at that moment in life,” she said.

She was getting her nonprofit organization Orphan Kitten Club off the ground and working professionally with cat rescue organizations, helping them create programs dedicated to the most vulnerable cats: orphaned neonatal kittens, known as “bottle babies,” because without a mother, they must rely on being fed by a bottle to survive.

Someone she met through her work suggested that she follow a photographer on Instagram called @iamthecatphotographer, who, yes, specialized in photographing cats. Ms. Shaw was intrigued. “I was like, that sounds weird — how can someone be a professional cat photographer?” She forgot about the suggestion until, thanks to their overlapping worlds, the cat photographer showed up on her Instagram feed anyway.

“There was a photo on his page of him in an ugly Christmas sweater with his cat in a Santa hat, posed like a cheesy 1980s Sears family portrait,” she recalled. “It made me laugh so hard, and also I was like, wait, this guy is really cute.”

Mr. Marttila, 37, was living in Philadelphia; Ms. Shaw, 35, was in Washington. She sent him a message, asking if he would be willing to come to Washington to take photos of some of her foster kittens. She offered him lodging in her guest room.

“At the time I would have said it was just professional,” Ms. Shaw said.

“… But I knew what it was,” added Mr. Marttila.

On April 2, 2016, they met in Washington for dinner at Busboys and Poets. Ms. Shaw figured at best there might be a fling: She didn’t have time for much else, and had a date with someone else planned for the following weekend. “I thought, OK, this is a cool guy to know,” she said. “We’ll take some photos, maybe we’ll make out, then he’ll go home and I’ll go on my date next weekend.”

Instead, they connected over their obvious love of animals, but also on issues that had nothing to do with kittens. Ms. Shaw was impressed by what she describes as Mr. Marttila’s “serious depth.”

“It was something I understood right away and now I have seven years of evidence,” she said. “He is a self-reflective person who has done a lot of work to grow and become this stable, introspective person who is a really good partner.”

They couldn’t stop talking, so Mr. Marttila stayed the weekend. He said he wished she didn’t have a date planned for the following weekend, because he wanted to invite her to an event he thought she would be the perfect plus-one for: a red-carpet movie premiere for Jordan Peele’s comedy film “Keanu,” about a kitten kidnapped by gangsters. Some live, adoptable cats would be walking the red carpet with gold chains on, and Mr. Marttila had been hired to shoot the scene.

Ms. Shaw wondered aloud if she should cancel her date so that she could attend, and settled on flipping a coin in order to decide. The coin said to cancel, and so for their second date, they met Mr. Peele.

Mr. Marttila had found his way to feline photography almost accidentally. In 2011, while pursuing a bachelor’s degree in neuroscience at Temple University, he started taking photos of his new cat and posting them on Instagram. As the number of people liking his photos increased, he expanded to photographing other pets to supplement his income.

“When I graduated I said, ‘OK, I am going to try to do this for a year, and if I am broke then I will go to grad school,’” Mr. Marttila said. Instead, in 2015, he landed his first book deal, for “Shop Cats of New York.” He met Ms. Shaw a few months before the book published by Harper Design.

The two quickly found synergy in their love for cats and began inspiring each other’s work. “When I met Andrew I was thinking I wish I could just focus on writing a book about kitten welfare, and then Andrew had a book coming out and it was so cool to see another young person really doing these things,” Ms. Shaw said. “I was looking at getting another job, but Andrew was the one who said to me, ‘Just try for three months.’”

She said having someone believe in her enough to say “just try” shifted her perspective. “I already had this passion for something that there was no job for, and so that made me go and create it myself.” Mr. Marttila said that Ms. Shaw renewed his passion for animals as well, and that her hustle inspired him to amp up his own work ethic. They say they are each other’s “hype person.”

After 10 months of dating long-distance, Ms. Shaw told Mr. Marttila that if he wanted their relationship to continue, he would have to move to Washington. “So I rented a U-Haul on Valentine’s Day 2017 and moved in,” Mr. Marttila said.

“Andrew told me when we met that his dream was to be a stay-at-home cat dad,” Ms. Shaw said. “And I was like, I have a lot of dreams in life, so I think I can make that happen.”

After about a year and a half of living together, they realized that with both of them working from home, three pet cats between them, and a room dedicated to foster kittens, they had outgrown their space. “We were like, where do you live when you can live anywhere?” And in August 2018, they started over in San Diego.

On a trip to Thailand in February 2019, after kayaking out to an uninhabited island, Mr. Marttila proposed to Ms. Shaw. “Even from that first date, I knew that I had met someone that shared the same paradigm that I did,” Mr. Marttila said.

Both live an alcohol-free, vegan, animal-friendly lifestyle, so when it came time to plan a wedding, those values became guiding philosophies for the event. They chose a friend’s animal sanctuary as the setting, because it’s a place where animals get to live their best lives. “I think it’s a significant space,” Ms. Shaw said, “because it’s about how amazing it is when you give someone the promise of sanctuary — and shouldn’t a relationship be like that?’

Ms. Shaw and Mr. Marttila were wed April 2 at Farm Animal Refuge in Campo, Calif. Their friend and veterinarian, Dr. Rachel Wallach, who was ordained for the occasion by the American Marriage Ministries, officiated, and the internationally renowned harpist Mary Lattimore played a version of the Cure’s “Friday I’m in Love” during the processional.

Afterward, 100 guests enjoyed a mocktail bar and an all-vegan meal of crispy squash blossoms, braised tempeh, beet chicharron and saffron cavatelli. Guests were then invited to take their edible vegetable basket centerpieces of zucchini, tomatoes and kale and feed them to the farm’s animals.

As a special surprise, Ms. Shaw presented Mr. Marttila with a basket of calico kittens — their new foster pets. As he cradled the tiny babies, Ms. Shaw leaned in to hug him. Mr. Marttila’s eyes welled up as he said, “This is a dream come true.”

On This Day

When April 2, 2023

Where Farm Animal Refuge, Campo, Calif.

An Unusual Ring Bearer The ring was carried down the aisle by Hugo, a pig that Mr. Marttila and Ms. Shaw rescued as an emaciated newborn from behind a taco stand in Los Angeles. Hugo looked dapper in a white collar with a black bow tie. To motivate him down the aisle, popcorn, his favorite treat, was dropped by the flower girl.

A Watermelon Toss In lieu of a bouquet toss, the couple chose to throw a watermelon together over the fence and into the pig corral. The melon landed with a crash on the ground — the trigger sound that sends happy pigs racing for a bite of the juicy snack. There was more than enough snacks to go around, as the couple had set up an imitation farm stand of vegetables and fruit that guests could offer the animals as well.

Woolly Wedding Crasher In organizing the layout of the wedding, the couple arranged for one part of the space — where the human food and drinks were served — to be left inaccessible to animals. A large sheep named Joey didn’t get that memo. He managed to crash the wedding, skirting by barriers and breaking into a frolic through the off-limits zone. As the bride, groom and guests tried to corral the sheep, they were outsmarted: he snatched a flower arrangement from one of the tables and proudly took off.