Published: Oct 25, 2013 11:45 PM EDT

LEE COUNTY, Fla. - A fired social worker is talking to WINK about the tragic death of a Lee County toddler. Karleen Halfmann said she worked on the case of three-year-old Michael McMullen who died last weekend after being wrapped and smothered to death in a blanket.

Halfmann said she's been a social worker for 17 years. She maintains that  she, along with her Case Manager did all they could to help McMullen's family. But, she said it's difficult when you're not told who is frequenting the home.

"When I first was told that the child had died, it felt like I got punched in the stomach," Halfmann said. "I dont know this child. I never met this child, it doesn't matter. It still hurts talking about it right now. I have a child that's roughly the same age and it's just really senseless."

While she didn't want to appear on camera, Halfmann said she worked for Lutheran Services for seven years and was promoted to Lead Supervisor two months ago. She said she supervised the Case Manager who worked directly with the Michael McMullen's family. "I think that my Case Manager did an excellent job," Halfmann said. "She is a very good social worker. She did what she could with the information she had. It's hard to safety plan a home or a family when you're not sure who is living there or frequenting the house."

The Lee County Sheriff's Office said the boy's "god mother" Donella Trainor, wrapped him tightly in blankets and tied the ends down as a form of discipline which ultimately, killed him. Trainor, along with the toddler's grandmother Gale Watkins and step father Douglas Garrigus are charged with his murder.

"It's hard to figure out," Halfmann said. "you do assessments all day long and you try to make your best decisions with regards to safety but you unfortunately, once we leave that house, we can't be there 24-7. We can't move in with these people to ensure the children are safe."

Halfmann says she and her case manager were fired this week as a result of the child's death. She's trying to understand what more could have been done. "I wish I could have said goodbye to people. I wish I could still be helping some of those families," Halfmann said. "Social work is what defines me and probably, after this incident, I will not be doing social work anymore."

Lutheran Services of Florida released this statement saying in part:
"The initial review determined two LSF employees failed to follow policies. They were immediately terminated. While these policy violations did not cause the death of Michael, LSF will not rest until all questions are answered so we can ensure the safety of children in our care."