‘We are Completely Overwhelmed’ (Exclusive)

• Ezra Toczek, 5, is suffering from end-stage liver disease and is in need of a liver transplant
• While he remained on the transplant list for the past few months, his former preschool teacher, Carissa Fisher, applied to be a living donor
• Ezra’s mother, Karen, exclusively tells PEOPLE how “overwhelmed” the family is by Fisher’s act

Five-year-old Ezra Toczek is receiving the ultimate gift from his former teacher.

The young boy suffered liver damage at birth and has since been fighting ongoing health challenges, leading to his recent diagnosis that his liver is failing due to end-stage liver disease.

But Ezra has been given a beacon of hope since joining the transplant list in February. His former preschool teacher, Carissa Fisher, learned of her student’s condition in March, and without letting Ezra’s family know, she applied to become a living donor. (A living-donor liver transplant occurs when a patient with a healthy liver donates a portion of theirs to someone whose liver no longer works properly, per the Mayo Clinic.)

Fisher applied following the trek Ezra and his mother Karen took from Western New York to New York City, where they learned he was in desperate need of a liver transplant. 

After Fisher’s application was submitted, she also traveled to New York City, where she underwent the required testing. After weeks of waiting, Fisher learned on Friday, May 24, that she had been approved to donate a portion of her liver to help Ezra.

Fisher didn’t wait long to share the good news with the Toczek family, and by Saturday, May 25, she headed straight to the family’s home with a stuffed animal, balloons, and a sign in tow sharing the great news.

“We are completely overwhelmed with her kindness and generosity and sacrifice, and it keeps hitting us unexpectedly that it’s really happening and we’re really going to be able to move forward, and we’re so grateful,” Karen exclusively tells PEOPLE. 

She explains to PEOPLE that there are no set dates regarding the transplant because, “Carissa is required to sit through a two-week ‘reflection period’ before the donor team can work with her to schedule a date for surgery.”

As for Ezra’s condition, Karen tells PEOPLE he “is hanging in there.” 

“We are very fortunate that they were able to get him approved to be listed when they did, rather than waiting until he’s critically ill,” Karen shares. “He has struggles, fatigue, sleep difficulties, and days where he just isn’t feeling well, but overall he is a trooper, and finds joy and every day.”

After seeing Carissa Saturday, Karen shared the news on Facebook later that day. “My brain literally couldn’t process what I was reading until she said it out loud. Miss Carissa is a perfect match! I can’t even begin to express our gratitude!” 

She continued: “The tears keep coming, and though I knew we’d be relieved to get the news eventually, I had no idea just how it would hit me! There has been no shortage of love, generosity, and genuine kindness from our family, friends, and community – but this?  The most amazing gift!!”

“You never know who’s life you are going to be changing,” Fisher told WKBW. “It was emotional. It made me very happy to see both of them happy.”

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Along with Karen’s Facebook post, she has shared the update to the GoFundMe page raising money for her son’s transplant. She shared the exciting news on Tuesday, May 28 and concluded the post by adding, “Thank you for your continued support – we have a long road ahead of us, and it’s getting real now.”

In addition to Karen’s GoFundMe, Fisher has also begun raising money in a separate GoFundMe page, which will raise money “for flights, food, lodging and other travel expenses for me and my caregivers that will be there with [her] helping through the [donation] process.”