2 Children With Rare Disease Who Live 300 Miles Apart Finally Meet for Special Playdate

Molly and Robbie are the only two confirmed cases of the disease in the United States.

Imagine traveling 300 miles for a playdate. For two families, it is a crucial way to find support and comfort as their children battle rare diseases.

Read: Bikers Show Up to Surprise Teen With Cerebral Palsy for His 13th Birthday

Kevin and Angela Duffy, both 33, live in Philadelphia and bring their daughter, Molly, for a playdate with her best friend, Robbie, who lives in Boston with her parents Kacey and Chris Edwards, 38 and 41 respectively.

The 3 years olds share a special bond because they are both battling the same debilitating genetic disease called Spastic Paraplegia Type 47 also known as SPG47 — a disease that causes mobility problems and learning disabilities. It's so rare that there are only 11 reported cases in the world.

Molly and Robbie are the only two confirmed cases in America. 

“SPG47 is present at birth and causes severe, progressive spasticity and muscle weakness, especially in the lower limbs," the Boston Children’s Hospital, which treats cases of the disease, says on its website. "In infancy, children with SPG47 have very low muscle tone (hypotonia). As they grow, they develop spasticity (tight, stiff muscles that make movement difficult), together with cognitive deficits."

“It's a condition that looks like cerebral palsy," Dr. Basil Darras, who has treated both girls at Boston Children’s Hospital, told Inside Edition:

He added that the muscles "become very stiff and tight it becomes difficult to walk."

Dr. Darras said: "While we have no cure for SPG47, patients that have it, have a normal life span."

There are treatments to help patients through the worse symptoms. 

“Physical, occupational and speech therapies can help children develop and preserve motor and communication skills," according to the Boston Children's Hospital said. "Muscle relaxants and Botox injections can help relieve spasticity in the muscles, and physical therapy can increase strength and range of motion."

The families of Molly and Robbie found each other on a Facebook support page.

"One day we got a message from Kasey saying, 'My daughter has Type 47,’ and we just couldn't believe it and we haven’t stopped talking since," Angela told Inside Edition.

The toddlers have had a series of online playdates and met for the first time in the fall. Inside Edition was there as Molly and Robbie got together for a day in Boston.

Read: College Basketball Player Given a Scare by Campus Officers Before He's Awarded Scholarship

Both girls have great dispositions — they love music, and love to dance.

When they got together for the play date, the parents bonded just like their daughters.

Kevin told Inside Edition: "There are days when it is really, really hard but she is so happy and she is the light of our life. There is no way we can stop fighting for her."

Chris echoed that sentiment saying: "We are not going to give up on our daughter."

Kacey broke down in tears explaining "if she wants to try skiing, she can I will help her. If she wants to go on a hike, I will help her, I will carry her. That is what we will do and make sure she can do everything she can." 

The parents have started a nonprofit called Cure SPG47, for more information and how you can help, click here.

Watch: Boy With Cancer Raises Nearly $7,000 for Other Sick Kids Through Hot Chocolate Stand