WESTPORT — Less a business than a familial institution for local pet lovers, Earth Animal celebrated the opening of its new store on Sunday afternoon.

Hundreds of people — many with dogs in tow — paid a visit to the new location at 925 Post Road East that formerly housed Starbucks. The store had previously been a half-mile west near Dunkin Donuts.

Festivities, including food, live music, lectures and a ribbon-cutting ceremony with local officials, drew a multitude of longtime customers who eagerly shared their deep affection for a 40-year-old family-run business they say has had a profound impact on their lives.

“They’re not just selling products,” said Susan Altschuler, of Weston. “They’re on the next level.”

She shared how, after learning her dog had cancer, she discovered the store and its focus on chemical-free food and products. In the process, they taught her lessons about animal health care and preventative medicine, which she now exercises with her current dog.

“I found out after the fact about all the things that we should have been doing,” she said.

Earth Animal grew out of the experience of Dr. Bob Goldstein, a veterinarian, and his wife Susan, a nutritionist.

“They were seeing a lot of cancer patients,” explained Stephanie Bolo, vice president of marketing and sustainability, in his practice in Yorktown Heights, N.Y.

“They started realizing it was the use of pesticides and chemicals on pets,” she said, including flea and tick medicines. They, in turn, opened the first iteration of the product business — Lick Your Chops — which was attached their veterinary hospital.

“We’ve been residing as a business in Westport for 35 years,” said Susan Goldstein, noting this new store was “25 years in vision.”

“It’s a go-to for pet parents and families who are seeking a kinder, better way for dealing with health and wellness issues,” she said, “and we just feel so honored to be here with such good friends.”

“Five years ago we started Earth Animal Ventures,” said COO Chris Moore, noting their products are now available in 6,500 retail stores throughout North America. “And we’ve just started our international expansion.”

“This is my parents’ dream come true,” said Merritt Goldstein, who has overseen the retail store for close to two decades. “It’s been a beautiful experience. The loyalty for the last 40 years has been very special.”

The new store includes a memorial brick walkway at the entrance dedicated to Merritt’s former co-manager John Mancinelli, who worked with her for 18 years and died two years ago.

“This outpouring is incredible,” said state Sen. Tony Hwang, who aided in the ribbon cutting. “Your love and affection for this town is demonstrated in everything you do in your store.”

“We’ve been coming here for a long, long time,” said Jan Colabella, of Westport.

“Everything is organic and safe,” she said. “They give us good advice. ...We’ve had four dogs since we’ve been coming here and they’ve helped us through everything.”

“This is a long-standing local business that’s loved by, and supported by, Westporters,” said Selectman Jennifer Tooker, who took part in the ceremony, “and they’re so grateful for their contribution to the community.”

“It’s about love,” Merritt said. “It’s about trust and it’s about friendship. That’s what Earth Animal is and we’re very, very blessed.”