Pete Rosengren successfully saved the boy and his own sons before going under the water off the coast of Florida in Miramar Beach earlier this year.
"The infamous friend group in high school," said Christa Hansen, as she and fellow friend Katy Ripp pour over photos, reminiscing about the good old days.
"Here's Pete, Katy and myself amongst the crew," Hansen said, pointing to one of the photos.
The 1996 Middleton High School grads are missing a big part of that crew, WMTV reported.
"If I could hug him one more time, I would say health thing full. I was to have him in my life," Ripp said.
Rosengren, 42, died in March while on vacation in Florida with his wife and three sons.
"It's not just heartbreaking, it's soul crushing," said his mother, Gayle.
Gayle said her three grandsons ran into the Gulf of Mexico and a strong rip current pulled them off shore.
"The boys had run ahead and one boy in particular got into trouble," she said. "He went out too far."
Rosengren's boys were able to get out of the water safely, but another boy was struggling.
That's when Rosengren rushed into the water and kept the boy calm until more help could arrive, but he went under and never came up.
"All I remember is saying, 'No, no, no,' louder and louder, screaming in the end," Gayle said.
The conditions in the Gulf of Mexico that day were so rough that beach officials closed the waters to the public.
"It was, it was devastating," Hansen said. "It was so shocking. Gives me the chills to just talk about it."
Rosengren was a man known for his smile and his world class hugs.
"He held on a little bit longer," Ripp said, "and it was just a big, a big Pete hug. So I wish I could hug him one more time."
Now, he is remembered as a loving husband, a devoted father and a hero who will never be forgotten.
Rosengren lived with his family in the Chicago suburb of Batavia. He and his wife has just celebrated their 18th wedding anniversary the Monday before the tragic accident.
Rosengren was also the Vice President of Sales and Digital Strategies for the Daily Herald Media Group.
A fundraiser for Rosengren's family is planned in Cross Plaines, Wisconsin, the town where he went to high school.
ABC7 Chicago contributed to this report.