Meet 8 precious kids who have rare diseases — and learn all about them.

They may not be common, but a whole lot of people are affected by rare diseases.

A disease is considered rare in the U.S. when fewer than 200,000 people have it at any given time and in Europe when it affects fewer than 1 in 2,000 people.

In the EU and U.S. combined, as many as 60 million people may experience one — because there are around 7,000 known rare diseases.

Ceridwen Hughes, a U.K.-based photographer, has a particular interest in rare diseases because her son Isaac was born with one.

Hughes, frustrated with the assumptions people made about Isaac based on his appearance, decided to start a community she called Same But Different. "I very much wanted people to see the person behind the condition," she told Upworthy.

She later launched a photo series called the Rare Project, where she captures photos of children with different rare diseases and helps them tell their stories. She puts a great amount of care into taking several photos of each subject and learning about their histories, struggles, and triumphs from their parents.

To further the spread of awareness, Hughes shared with us the following eight photos she took of children with rare diseases.

Below each is a brief description of the disease and, in some cases, a little info about the children. You can click through to read more about them. Up first is her son Isaac!

1. Isaac, who has Moebius syndrome

All photos belong to Ceridwen Hughes/Same But Different and are shared here with permission.

A rare neurological condition that affects facial muscles by weakening or paralyzing them, Moebius syndrome makes it impossible for the person to smile, frown, or raise their eyebrows, among other limitations. The muscle weakness also makes it difficult for babies with Moebius syndrome to eat.

2. Grace, who has periventricular leukomalacia (PVL)

PVL is a rare condition where the white matter in the brain dies due to a lack of oxygen or blood flow. Babies don't usually have symptoms, but as children get older, they are "at risk for motor disorders, delayed mental development, coordination problems, and vision and hearing impairments."

Grace also has some other health conditions in addition to PVL. "Grace is a wonderful child whom we love very much," her mom told Same But Different. "We encourage her to try everything and allow her to make her own decisions (within reason!)."

3. Mari, who has WAGR syndrome

Touching 1 in 500,000 to 1 in a million people, WAGR syndrome is a disorder that affects many of the body's systems. In Mari's case, she has experienced a bowel malrotation, seven tumors that required surgery and radiation, and eye surgery. She is legally blind.

“It is very rewarding having such a lovely little girl who has overcome so many hurdles and is coming on in leaps and bounds," her mom Caryl told Same But Different. "We are so proud of her and she constantly amazes us with her capabilities despite her difficulties.”

4. Jake, who has Angelman syndrome

A complex genetic disorder that mainly affects the nervous system, Angelman syndrome causes "delayed development, intellectual disability, severe speech impairment, and problems with movement and balance." Jake wasn't diagnosed until he was 7 years old.

"Most people who meet Jake are greeted with a hug but then they struggle to communicate with him. His smile says a thousand words," his mom told Same But Different. "I think it is important that people have a better understanding of rare diseases. I believe that with greater awareness there will be more acceptance. "

5. April, who has Hurler syndrome

Hurler syndrome is a genetic metabolic disorder that prevents the body from breaking down glycosaminoglycans, which are long chains of sugar molecules, because of a missing enzyme. Without it, glycosaminoglycans build up in the body and damage internal organs. Hurler syndrome is treated with IV enzyme replacement therapy.

6. James, who has Coffin-Lowry syndrome

Affecting 1 in 40,000 to 1 in 50,000 people, Coffin-Lowry syndrome presents differently in boys and girls. Boys with the genetic disorder suffer from "severe to profound intellectual disability and delayed development." James, who is nonverbal, can sometimes feel frustrated when others don't understand him. That makes every day more challenging because he cannot communicate his needs, such as hunger and thirst. He also has low muscle tone and low mobility.

"James is our little boy and all we want is that as he grows older he is accepted just the same as any other child would be," his parents told Same But Different. "He has so much to give and the world is definitely a better place with him in it."

7. Isabel — HSV encephalitis

HSV-1 encephalitis is a rare but dangerous condition in which brain inflammation results from the virus that causes cold sores. Isabel, who was diagnosed at 13 months old, had a stroke as a result, which caused a brain injury. She has epilepsy, a hearing impairment, is nonverbal (but communicates with an assistive device), a developmental delay, and autism.

"She is strong willed and independent, she is absolutely perfect in our eyes and the sunshine in our lives," her parents told Same But Different.

8. Percy, who has Prader-Willi syndrome

Around the world, between 1 in 10,000 and 1 in 30,000 people are born with Prader-Willi syndrome, a genetic condition. As a baby, these individuals usually have weak muscle tone, feeding difficulties, poor growth, and delayed development. As they grow, they develop an insatiable appetite that leads to obesity and they often experience intellectual and learning disabilities as well as behavioral issues.

Percy's parents are preparing for the challenges his extreme appetite will bring by moving all food to a locked portion of their home and by installing a surveillance system so that if he tries to leave the house in search of food, they'll know. "{W]hen we were given his diagnosis we were devastated but in some strange way a bit relieved as his diagnosis could have been so much worse," his parents told Same But Different.

Hughes has found that even though these children's diseases are different, their families can find strength by supporting one another.

"[U]ltimately we all share the same fears, difficulties, and challenges no matter what the rare disease is," she told Upworthy.

And for the rest of the world, she's hoping to help others understand that medical differences aren't reasons to stare, mistreat, or make assumptions.

"If everyone could know one really important thing about rare diseases, it would be that everyone deserves kindness," Hughes said. And by shining light on the children, their conditions, and their personalities, she's helping educate others and make the world a better place — for all of us.