When Tiffany Moreno is out with her 4-year-old son, people sometimes assume they’re siblings because they are so close in height.

Moreno, who stands 3 feet 11 inches tall, turned to Facebook last year in hopes of finding an organization devoted to people her size.

“I was born and raised here, and before I found this organization, I only met like two other ‘little people’ in my whole entire life on this island and that was it,” said Moreno, 25, who grew up in Ewa Beach. “It’s good to feel that it’s not only me.”

The group she discovered online is Ka Po‘e Li‘ili‘i o Hawaii, the Hawaii chapter of Little People of America, a nonprofit organization devoted to people with dwarfism, defined as a medical or genetic condition that results in a height of 4 feet 10 inches or less.

Now she and other leaders of the small Hawaii chapter are trying to reach out to more little people and their families and friends who might want to connect and learn from one another’s experiences.

The group is staging its 20th Anniversary Celebration at the Hilton Waikiki Beach Hotel on Saturday, from 9 a.m. to 4 p.m. The event costs $15 and includes music, lunch and activities for all ages.

Attendees will hear from a national expert in the field of skeletal dysplasia who also will meet with families in individual sessions. The featured speaker is Dr. William G. Mackenzie, chairman of the Department of Orthopedic Surgery at Nemours/Alfred duPont Hospital for Children in Wilmington, Del., and chairman of the Medical Advisory Board for Little People of America.

“We meet people to talk to them about their medical issues,” Mackenzie said in a phone interview. “I’m not there as a treating physician; I’m there as a counselor to help them understand their problems and how they can be managed.”

Hawaii chapter President Maria McClellan invited Mackenzie because she wants other little people in Hawaii to have access to his expertise. She has Morquio syndrome, a progressive metabolic disease, and sought him out for treatment that included neck fusion surgery.

There are hundreds of kinds of skeletal dysplasia, the medical term that covers dwarfism. By far the most common is achondroplasia, which results in short arms and legs but average-size torsos. The genetic condition affects 1 in 7,000 people in the United States, Mackenzie said.

Most children with dwarfism — roughly 80 percent — have average-height parents and siblings. That’s the case for both Moreno and McClellan.

“I’m the only short one in my family,” said Moreno, who weighed just 2 pounds when she was born. “My mom says I was the size of a soda can, basically.”

She has an extremely rare form of dwarfism known as Russell-Silver syndrome, a congenital condition that causes poor growth.

McClellan, on the other hand, said she was so long and slender when she was born that “the midwife said I would be a model.” Later she was diagnosed with Morquio, and now at age 26 she stands 3 feet 2 inches. Her brother, however, is a 6-footer.

A student at Kapiolani Community College, McClellan has been studying American Sign Language and is taking an online course on “law for the disadvantaged.” She uses a Dragonmobility power wheelchair that pivots and lifts her from floor level to eye level, as needed. She also has a service dog, Shadow, a gift from Assistance Dogs of Hawaii, who picks things up for her and knows 90 commands.

Moreno, a Campbell High School graduate, is married and has her hands full with her son, Legacy, and working as a preschool teacher’s aide. She uses stools to reach things and relies on TheBus and Handi-Van for transportation since she doesn’t drive.

They both say their size has made them more empathetic.

“I see people in a different way,” said Moreno, who is vice president of the Hawaii chapter of Little People. “I have to put myself in their shoes. A lot of times when I meet people, they don’t put themselves in my shoes.”

And the two women see other pluses to their situation as well.

“One thing you can save money on is clothes,” McClellan said, raising her dark eyebrows with a knowing look.

“Yeah, my shoes are a LOT cheaper,” agreed Moreno, whose feet are the size of a preschooler’s.

“But the downside is I never got to go on those roller coasters,” McClellan sighed.

Bit by bit, American society is letting go of myths that date back to the days when people with unusual physiques were displayed as circus acts. Asked what are common misconceptions, Mackenzie reeled off a few: “Dwarfs are stupid, dwarfs are circus people, dwarfs die early — there are a lot of misconceptions,” he said.

In fact, the majority of little people have normal intelligence and life spans, he said. Most enjoy good health, though some need medical treatment or surgery to address complications resulting from dwarfism, such as orthopedic problems.

“I think, for the most part, society in general has more information and more understanding about forms of skeletal dysplasia,” Mackenzie said. “Many people with skeletal dysplasia don’t feel that they are abnormal. They feel they are just part of the wide genetic spectrum.”

Some families with dwarfism have shared their experiences on television to help break down barriers, including “The Little Couple” on TLC, which follows Dr. Jen Arnold, a neonatologist, and her husband, entrepreneur Bill Klein. McClellan found out about Little People of America by watching another TLC show, “Little People, Big World,” in high school.

Dwarfism is covered as a condition under the Americans With Disabilities Act, and Little People of America is advocating nationally to ensure that ATMs, gas pumps and other facilities are accessible.

McClellan and Moreno say people in Hawaii are generally respectful and that they haven’t had to deal with name-calling or bullying.

“Whenever anybody stares, I just say hi to them,” McClellan said. “And then they kind of like break out of it and they go on. Or they say hi and they start to ask questions. Little kids are curious because they see this person who’s as short as them who looks older, and they can’t figure it out. I’ve been offered to play toys with them.”

Moreno got a lot of double takes and questions when she was pregnant. People would say things like, “Oh, you’re having a baby — can it fit?” She told them she would be having a cesarean section. Russell-Silver syndrome is a rare mutation that happens in the womb, and she knew it was highly unlikely to occur in her baby, and it didn’t. Her husband and son are of average height.

“I think generally, when people see somebody and they look physically different from them, they have a lot of questions,” Moreno said. “I answer people’s questions. This is what it is. This is what can happen. It’s not like they’re being rude. I think they are just generally curious.”

Little People of America has about 5,000 members across the country, including friends and family, according to its website. The local chapter has about 20 members on Oahu.

McClellan’s mother, Gemma Yamamoto, hopes families with young children who have dwarfism will come to the anniversary event. It will give parents, siblings and others a chance to trade stories, share logistical tips, learn more about medical options and build a sense of community.

“I noticed at least with Maria, her curiosity started when she was quite young,” Yamamoto said. “The answers were found through meeting other people.”