Anthony DeNicola does everything he can to keep the memory of his son, Joseph, alive.

The 7-year-old died Nov. 4, 2014, just days after going into anaphylactic shock on Halloween. DeNicola, of Staten Island, has created a nonprofit, Joseph's Helping Hand, to raise awareness of severe food allergies, from which Joseph suffered all his life.

He also has a tattoo on his arm that commemorates the last time he held his son’s hand. The poignant moment took place as doctors prepared to wheel Joseph into surgery to harvest his organs after the boy was declared brain dead.

"I'm very proud of it," DeNicola told the Staten Island Advance about his tattoo. "I look in the mirror every day, and I'm still holding my son's hand."

According to Joseph's story on the Helping Hands website, he began having problems with allergies almost immediately after his March 2007 birth. Eventually, he was diagnosed with severe allergies to milk, milk proteins, whey and hazelnuts.

"This is where it all started," his father wrote on the website. "We had to read the ingredients in everything we bought."

When Joseph outgrew baby formula, he had to drink soy milk. His family also grew accustomed to carrying around an Epi-Pen and Benadryl wherever they went.

Even smelling food that contained an ingredient he was allergic to could send Joseph into anaphylaxis, his father wrote.

On his final Halloween, Joseph went trick-or-treating with family and friends. At a party later that night, his cousins had regular pizza in one room and Joseph had a specially-made pizza in a separate room.

Despite all the precautions, Joseph, whose asthma had been acting up that week, required a breathing treatment with his nebulizer when he got home, his father said. As his breathing worsened, two Epi-Pens failed to bring him out of the reaction, so his father and a neighbor rushed him to the hospital.

"At 5 o'clock, we were trick-or-treating, and at 7 o'clock, we were in the emergency room," DeNicola told the Staten Island Advance shortly after Joseph's death.

Joseph suffered cardiac arrest in the emergency room, his father said. His brain was deprived of oxygen for 20 to 30 minutes and, four days later, he was declared brain dead.

Joseph's doctors said his cause of death was a "one-two punch of asthma and allergies together," DeNicola told the Advance in 2014. Though no one saw Joseph eat anything he shouldn't the night he got sick, DeNicola said the smell of the wrong food or someone failing to wash their hands around the little boy could have triggered his fatal allergic reaction.

After his death, his donated organs saved the lives of five other people, his website said.

“Joseph was always a giving little boy,” his father wrote. “If there was a line for something, Joseph would let everyone go first and he would wait quietly for his turn. He never complained.”

The DeNicola family said that donating Joseph’s organs was one of the best things they ever did.

"It gave us peace and comfort to know that Joseph lives on through all of the people he saved," the website said. "In life, he was always giving. He will continue to give through his foundation, through education and research on allergies and asthma."