Charlotte and Gwenyth Gary
Organized by: Tom Cruise
In March, movie producer Gordon Gray and his wife Kristen learned that both of their daughters suffer from an incredibly rare degenerative brain disorder for which there is no cure. The producer – known for inspirational sports movies like The Rookie and Invincible – is now in a race against time to raise the $10-12 million needed to fund medical research he hopes will find a cure before the disease claims his daughters' vision, mobility and then lives. The couple, who live in Los Angeles, quickly founded the Charlotte and Gwenyth Gray Foundation and launched a social media fundraising campaign. "We need the money yesterday," Gray, 50, tells PEOPLE. "Every day is worse than the day before. It's a degenerative disease and we just need to get started now." An incredible network of celebrities – from Rihanna to Channing Tatum to Gwyneth Paltrow – have come out in support of their fundraising efforts by sharing the video they created on their social media sites and asking their millions of followers to each donate just $1. The support has been "incredibly overwhelming but incredibly empowering," Kristen, 39, tells PEOPLE. An 18-Month Medical Odyssey In September 2013, the Grays' older daughter, Charlotte, now four and a half, began having trouble speaking. Over time, the parents watched their little girl's ability to communicate degrade "from 8-word sentences to 5-word sentences to mixing up words," says Kristen. After Charlotte began speech therapy, her parents still felt that something wasn't right. Over Christmas that year, the three-year-old began having muscle tremors and was taken to a pediatric neurologist. A year of misdiagnoses – from autism to epilepsy – followed until a relatively new DNA sequencing technology called whole exome sequencing finally solved the medical mystery for them in March. The doctor asked them to come into his office to receive Charlotte's latest test results in person. "At that point I sort of knew that the results wouldn’t be good, just knowing that they wouldn’t tell us anything on the phone," says Gordon. But it was still devastating to hear the diagnosis: a form of Batten disease called Late Infantile-NCL Batten Disease CLN6. The doctors said, 'It's rare, there is no cure and it's fatal,' " says Gordon. He and his wife emerged from the doctor's office in a daze and since then, "we've been on one continuous search for answers and for treatment," says Gordon. After learning that inherited genetic disorders often affect siblings, the Grays had their then 20-month old daughter Gwenyth tested and found out she suffered from the same exact genetic mutation. A Deadly Disease People who suffer from Batten experience blindness, seizures, personality and behavioral changes, dementia, the loss of motor skills and the ability to communicate according to the Batten Disease Support and Research Association. Children with the Grays' particular mutation of Batten die between the ages of 6 and 12. Although Batten was discovered in 1903, it's so rare that research and funding have been extremely limited. The Grays called doctors all over the world – and found that specialists were at best two to three years away from a potential treatment. "One of the doctors we spoke with said, 'I would recommend that you live in a single-story house and prepare for wheelchairs and blindness,' " says Gordon. "That's where we started." After experts around the globe told them there was nothing they could do for the family, the Grays began asking a different question. "Most of what we heard is, 'We're years away and it's probably not going to be able to help your daughters,' " says Gordon. "So our push was, 'How can we accelerate getting your treatment to humans?' " The answer? Money. "Because of the rarity of this disease it doesn't get a lot of attention," he says. "And because it doesn't get a lot of attention most of these doctors don’t get a lot of funding. We made it our goal – 'Well, you guys do the research, we'll get the funding.' " Since then that's where they've focused their efforts. "We're trying to raise money in the quickest way possible so that we can accelerate a cure and in curing our daughters we'll ultimately end up hopefully with a cure for the disease," says Gordon. Other Families Reach Out Since launching the foundation – and their social media blitz the last few days – the Grays have heard from other families affected by the disease, many of whom have already lost children. "I've had 10 to 15 families with kids who have degenerative brain disorders that are similar who have expressed hope in all that's been happening in the past couple of days," says Kristen. The couple is optimistic they'll be able to reach their goal and cure the disease – because failing is not an option. "Our plans are to cure our daughters," says Gordon. "We have to be optimistic that we're gonna reach the goal and ultimately save our girls and put an end to this disease." Once they do, they plan to continue the foundation's work to raise money for other rare diseases. In the meantime, even as Charlotte's condition worsens, she continues to inspire her parents with her caring spirit and love of life. "She loves to play and she loves to be playful and just always has a smile on her face," says Kristen. "That is something that has held strong through all of this and I think kept Gordon and I strong."