(CNN) When loved ones gathered for the funeral of Maison Hullibarger, they were supposed to hear uplifting messages and fond memories of the teen.
Instead, a priest told hundreds of mourners that suicide is wrong and repeatedly referenced the 18-year-old taking his own life.
Now, Maison's mother is suing Father Don LaCuesta, the Archdiocese of Detroit, and Our Lady of Mt. Carmel Parish in Michigan.
In the lawsuit, Linda Hullibarger requests compensatory damages for pain and suffering and punitive damages to punish the defendants and help prevent such "outrageous conduct" from happening again.
The Hullibargers barely had time to process their son's December 4 death when they met with the Rev. Don LaCuesta to discuss what they wanted in the homily.
"We wanted it to be about family. We wanted him to talk about loving one another, lifting one another up and being kind to one another. That's what we wanted the homily to be about," Linda said days after the funeral.
Maison's parents never told LaCuesta how their son died. And the priest never asked, according to the lawsuit.
So they were stunned when LaCuesta started condemning suicide in front of the mourners, which included Maison's five siblings and classmates.
"People in attendance, including many of their son's classmates, had no idea as to the cause of death and became visibly and vocally upset about hearing Father Laguesta reveal and discuss it," the lawsuit says.
"Father LaCuesta repeatedly discussed suicide and how it is condemned by the Church, how it is a secular crime, and how it is a sin against God with dire eternal consequences."
In an interview last year, Linda and Jeff Hullibarger described the shock that spread through the crowd.
"I looked at Jeff and thought, 'What is he doing?' " Linda said.
"We have five other kids. Nobody could believe it," Jeff said. "I looked at the parish, and everyone had the same look on their faces."
As the priest's words ripped open the family's wounds, Jeff Hullibarger tried to intervene.
"After the first few times that he said that word (suicide), I approached the pulpit and I told him, I whispered in his ear, 'Father, please stop.' "
It didn't work.
"He didn't miss a beat. He kept going," Jeff said. "He said that word another handful of times. It made the worst day of our lives more worse."
LaCuesta has not responded to CNN's request for comment about the lawsuit. The Archdiocese of Detroit said Wednesday it cannot comment on pending litigation.
But the archdiocese apologized to the family in a statement last December.
"We understand that an unbearable situation was made even more difficult, and we are sorry," the archdiocese said.
It said the priest will not be preaching at funerals for the foreseeable future, and "he will have all other homilies reviewed by a priest mentor."
"In addition, he has agreed to pursue the assistance he needs in order to become a more effective minister in these difficult situations," the archdiocese said. "This assistance will involve getting help from professionals -- on human, spiritual and pastoral levels -- to probe how and why he failed to effectively address the grief of the family in crisis."
According to a copy of the homily, LaCuesta said, "God can forgive even the taking of one's own life. In fact, God awaits us with his mercy, with ever open arms. ... Yes, because of his mercy, God can forgive suicide and heal what has been broken."
But he also said "we must not call what is bad good, what is wrong right. Because we are Christians, we must say what we know is the truth -- that taking your own life is against God who made us and against everyone who loves us. Our lives are not our own. They are not ours to do with as we please. God gave us life, and we are to be good stewards of that gift for as long as God permits."
The priest also spoke about the consequences of suicide.
"The finality of suicide makes this all the worse," LaCuesta said. "... Now you will have to work through this pain by yourselves, or with those close to you now who will need to lean on you even as you lean on them."
Maison's mother said she had no idea the priest would deliver a homily so drastically different from what the family discussed.
"He basically called our son a sinner in front of everyone," Linda Hullibarger said. "We had no idea that he was going to do this. ... We've been lifelong members of the church."
The archdiocese said LaCuesta was trying to offer a message of confidence in salvation.
"We acknowledge, however, that the family wanted a homily based on how their loved one lived, not one addressing how he passed away," the archdiocese said.
"We also know the family was hurt further by Father's choice to share church teaching on suicide, when the emphasis should have been placed more on God's closeness to those who mourn."
After LaCuesta's homily, the priest was supposed to turn the floor over to the parents to deliver their remarks, Jeff Hullibarger said.
But the priest didn't let the parents speak. Instead, "he proceeded to end the funeral, and the music started," Linda Hullibarger said. "We had to stop the funeral director because everyone just stood up."
The funeral director stopped the music, and the parents were able to honor their son the way they wanted him to be remembered.
"We would like to celebrate the life of Maison," the parents said. "He has had a great impact on the lives of many people. Passionate and opinionated, that's what we loved about him.
"Our family's message for you today: Please be kind to one another. Reach out to those you care about. Show sincerity in your actions. And love forever, unconditionally."
The public heard those messages and acted on them.
The Hullibargers' GoFundMe page, which was established before the funeral, listed a goal of $10,000 to help pay for Maison's funeral and burial expenses.
Donors far exceeded that goal, contributing more than $23,000.
The Hullibargers said they're grateful for the outpouring of support. But they said their reason for speaking out is because they want LaCuesta to be dismissed, so no other family will suffer the way they did.
"We just don't feel that the consequences are where they need to be right now," the parents said. "We asked him (the archbishop) to remove the priest from the priesthood."
They also want to make sure the funeral doesn't overshadow the joy that Maison brought to his loved ones.
"Maison is a great person. He's a very caring person," his mother said. "We had numerous students come up to us and tell us how in their time of need he was there for them. ... He was just an unbelievable son."