Three can be a crowd. But when it comes to children, that's Katherine Heigl's lucky number.

"Three is enough," the Life as We Know It star told E! News in an exclusive interview, "and I don't think I can spread myself any thinner in this arena."

Suffice it to say, when asked if she envisioned more kids in her future, the answer was a "hard no" from the mom of daughters Naleigh, 14, and Adelaide, 10, and son Joshua, 6.

At one point, Heigl did think she "for sure" wanted another child, but quarantining during the pandemic a couple years ago "really clarified my decision," she said. "No more."

And so far we've only addressed the humans she shares with her husband of 15 years, musician Josh Kelley. "If I bring one more animal into this home," the 44-year-old deadpanned, "my husband will leave me, and then I'm alone with eight dogs, three cats and three children. So, we really need to avoid that."

Laughing, she added, "I need the partner and the help."

But if you're wondering how, even with help, she does it all—wife and mom, acting, rescuing animals, creating her dog nutrition brand Badlands Ranch—Heigl assured that she, in fact, does not. At least, not all at once.

"It's very much compartmentalizing," she said about managing the various aspects of her life. For instance, while she was shooting her Netflix series Firefly Lane in Vancouver, her kids were home in Utah sticking to their routine. "I can't easily anymore take them out of school systems and put them into whole new cities and environments," she explained. "I had to live with that aspect of what I do for work, I have to leave my family." So, when she's away from home working, she's "hyper-focused" on the job at hand.

"I call the kids probably two, three nights a week," Heigl continued. "I'm not FaceTiming every day—I'm at work, having crap cell service or terrible WiFi. You have to be able to let it go."

That being said, she cracked, "I'm sure I'll be paying for their therapy, and mine."

But all of the above means that, when she's at home, she's completely focused on being there and work is on the back burner.

"My manager, my agent, my lawyer, they're all like, 'Hey, you should probably read that script we sent you two weeks ago...'" Heigl said. "I'm like, 'Right, right, right, right...' I just hyper-focus on the world I'm in now."

After living in Los Angeles for two decades while making movies and starring on Grey's Anatomy, Heigl's world is now at her Utah ranch, where she's been able to enjoy a smaller community and slower-paced existence than if she'd stayed geographically closer to Hollywood.

"I could kind of decompress and let that hustle part of me go—a little bit," she said. "I don't know that in any career you can ever completely stop hustling, but being able to separate it a little bit and choose those times of hustle versus just being in it constantly was really important to me."

And, Heigl emphasized, it's a place that checked off a lot of boxes for her and Kelley when it came to where they wanted to raise kids.

"I didn't know how to raise them in L.A.," she said, "so I felt like I could do it here. I could be more on top of things that scare me and I could be more on top of the kinds of friends they have and places they're going, the kind of activities they're involved in—and what the hell they're doing on their phones!"

At least one activity everyone's involved in is tending to the family pets—though ironically, Heigl said, her three small dogs don't care much for the kids.

They're "very attached to me and I'm very attached to them, but they do not like the children," she explained. "They bark at them every time they come into a room, they don't want [the kids] to hold them—and what's really unfortunate is that they're really cute, they look like little stuffed animals, so of course the kids want to cuddle them and love on them, and they're like, 'Don't touch me.'"

Rounding out the pack are three older dogs that mainly "just sleep and hang out," Heigl said, and two Rottweiler puppies she rescued last August after they were left at a Los Angeles shelter. With help from the actress' Jason Debus Heigl Foundation, they were nursed back to health from bouts of parvo and she took them back with her to Utah to be fostered and then adopted...

"But now I love them so much I can't give them up," Heigl admitted. "And they are great with the kids—they're awesome family dogs—and they're great with the little dogs. And"—she paused a moment to curb her enthusiasm—"they're okay with the cats."

Naturally, it was an organic fit for the self-described "passionate animal person" to start Badlands Ranch, a line of dog food and treats formulated to address unseen health issues that can affect our canine BFFs. Utilizing input from holistic vets and pet nutritionists, it's a brand, Heigl described, "that I'm really proud of and can stand behind, and say, 'Yeah, we are adding something of real value to the pet nutrition world.'"

And, with the final season of Firefly Lane wrapped and premiering on Netflix April 27, Heigl is busy hyper-focusing on the home front. "At the moment," she said, "it's solely about the dog food, the children, the animals."

Though, if someone tosses the right script her way... she'll catch it.

"I would kill to do a 27 Dresses sequel," she said, addressing fans' ongoing hope for a follow-up to her 2008 rom-com co-starring James Marsden. Heigl was already on the record RSVPing yes to the possibility, and she reiterated that it would be "amazing" to check in with eventual bride Jane and groom Kevin, 15 years after their nuptials.

"We're talking a little bit about it," she added, "so, we'll see."

Not quite a save-the-date card, but we heartily accept the proposal.

—Reporting by Rebecca Ray