CHICAGO (CBS) — At only 24 years old, Dayna Less had a very bright future in front of her; a second year of her pharmaceutical residency at Mercy Hospital, and a June wedding to her childhood sweetheart.

“She was the best and brightest star on this planet, and she didn’t deserve what she got,” her father Brian Less said Tuesday, a day after Dayna was shot and killed while getting off an elevator at the hospital where she worked.

Dayna was one of three people killed by a gunman at Mercy Hospital on Monday. The gunman also was killed during a running gun battle with police.

“This is a very sad day, an impossible day for all of us,” her father said.

danya less 2 e1542733692905 Dayna Less, Pharmacy Resident Slain At Mercy Hospital, Had Unique Gifts; Brightest Star On This Planet

Danya Less was fatally shot by Juan Lopez outside an elevator during a shooting rampage at Mercy Hospital. (Credit: Less Family)

Regardless of how she died, her father made it clear he doesn’t want her remembered as a victim.

“I want everyone to understand that. Dayna was a very special person. She had unique gifts. She was intelligent, she was funny, she was kind, she was a good friend, and had good friends, and has good friends. She was wanting and willing to help other people for her whole life,” he said.

Dayna had graduated from Purdue University with a PharmD in May, and was in her first year of pharmaceutical residency at Mercy. She was planning to return to Mercy for her second year. She was also planning to get married in June to her fiancé, Adam Keric. Her mother was already making her wedding dress.

“Adam’s heart is broken, as all of ours are broken,” her father said. “What else can you say to a man who’s loved a person for 10 years, and decided to spend their lives together. He made her laugh, he made her giddy at every phone call, he made her complete, and he’s crushed. I don’t have any answers.”

Her father said Dayna and Adam had known each other since they were 9 years old. They started dating when they were 15, and never dated anyone else.

“It was a match made in heaven. We were planning a wedding of over 500 people, and I was going to be giving a wedding speech instead of a eulogy,” her father said.

danya less e1542733557976 Dayna Less, Pharmacy Resident Slain At Mercy Hospital, Had Unique Gifts; Brightest Star On This Planet

Dayna Less was fatally shot by Juan Lopez outside an elevator during a shooting rampage at Mercy Hospital. (Credit: Less Family)

Brian Less said the family was planning to spend Thanksgiving at his brother’s house, after losing his mother in law a few weeks before Dayna died.

“I don’t know how anybody in my family can think of holidays. Some day, but not now,” he said.

Brian Less said his daughter was the hardest-working person he ever knew, a trait she had since she was a teenager. When she was growing up, she suffered severe headaches, and at 15 had two surgeries at Georgetown University to treat trigeminal neuralgia. After her treatment, she and her mother started a blog titled “Dayna’s Story: My Daughter’s Headache” to help others who coped with the same condition.

“Dayna helped hundreds of children across the country, and internationally, who were inflicted with this disorder. She gave them hope, she gave them help, and she was a friend to them,” “Some of them didn’t make it, but she soldiered on, and she helped everyone she could,” Brian said.

While a pharmacy student at Purdue, Dayna and her classmates traveled to Kenya, and while they were there, doctors in Kenya went on strike. So Dayna and her classmates helped take care of patients at a hospital.

“She called me and said, ‘Sometimes I don’t know what I’m doing,’ and I said you do the best you can, and you’ll learn the most you can out of those types of situations,” her father said. “She understood that, and she agreed, and she did the best that she could.”

danya less 1 e1542733635283 Dayna Less, Pharmacy Resident Slain At Mercy Hospital, Had Unique Gifts; Brightest Star On This Planet

Dayna Less was fatally shot by Juan Lopez outside an elevator during a shooting rampage at Mercy Hospital. She recently graduated with a pharmacy degree from Purdue University. (Credit: Less Family)

Less and her father were huge Cubs fans. The team tweeted their condolences to Less and the other victims of the shooting, Chicago Police Officer Samuel Jimenez and Dr. Tamara O’Neal. A friend of Less’ replied, saying “One of her and her family’s favorite things together was celebrating their love for the Cubbies.”

The tweet included multiple pictures of Less and her family at Cubs games, even one of her as a little girl.

Three other people were killed in Monday’s shooting at Mercy Hospital, including the gunman. Police have said the violence started outside the hospital, where 32-year-old Juan Lopez shot and killed his former fiancée, Dr. Tamara O’Neal, before bursting into the hospital, where he killed Less and Chicago Police Officer Samuel Jimenez, who responded to the shooting.