In Illinois, thousands of people have been detained by federal immigration agents since President Trump took office nearly one year ago.

Many families have been left behind to pick up the pieces.

Kimberly Perez's father, 60-year-old Carlos Perez Ruiz, was detained in north suburban Niles in September, and his family is still fighting to get him released.

"He wants to be out, he wants to be free," she said. "He wants to be with his baby girls, his granddaughters."

Ruiz was detained on Sept. 27, while waiting at a bus stop on his way to work.

"He's very caring. He has a great heart. He's always said that I've always been his world," she said. "I told him to, you know, be careful not to go out, but that day he did decide to grab the bus."

She later got a call from a number she didn't recognize, and something told her to answer.

"I usually don't answer numbers I don't know, and something told me to answer, and that's when my dad told me not to freak out, that everything was going to be okay, that he was just going to be sent to Mexico that coming Monday," she said. "I started screaming, as I didn't know what to feel. I felt so much."

When her father asked if he should sign the papers for a voluntary deportation to Mexico, she told him no.

"We're going to fight the years that you have been here," she said.

Ruiz has been living in the U.S. for 35 years.

"To have a better life. To get, you know, better jobs," his daughter said.

 Perez said it isn't easy to become a U.S. citizen. For over two decades, her father has been trying to do just that with the help of his brother, who is a citizen, through his I-130 sponsorship, also called a family petition. 

"They approached him and and asked him, 'Do you have papers?' and my dad said, 'I have … I don't have papers, but I have papers in process from my brother.' And they told him that those were garbage and that those were not good," Perez said. "This is exactly what he told me, yeah, over the phone."

After first being held at the ICE facility in Broadview, Ruiz is now being detained at an ICE facility in Michigan.

"He has lost a lot of weight," his daughter said. "His face is … used to be like all puffy, you know? Now it's all bony."

Perez said she makes the four-hour drive to visit him in detention every few weeks, along with her husband, Andrew Victor Carrillo, and their four daughters.

"They were scared at first. They were like, 'why are we here?' The oldest one, you know, says, 'Why is grandpa in jail? What did he do?'" she said. "I have to tell her, 'he didn't do anything.'"

A CBS News Chicago check found no criminal record for Ruiz.

"He has no criminal history. He had no interactions with the police. Him being here undocumented, that's, I guess, what they're calling the crime that he's being accused of," Carrillo said. "It's heartbreaking having to see Kimberly go through this every day. The legal fight has just been so, so difficult."

Perez said it's been difficult for her ever since her father was detained.

"I can't even rest, and it's been just stressful," she said.

Carrillo said, "it feels dehumanizing."

"Knowing that he was detained solely for the reason that he looks Hispanic," he said. "It feels like this country is, like, turning its back on the Hispanic community, the Latino community, when all of us just want to live in peace."

Perez said she can see the sadness in her children's eyes when they visit him.

"My dad tells them that he'll be home soon; that he'll be back and give them all the candies that they want," she said. "He wants to see them grow up, and that's really important to him, and I want him to see them grow up, too."

The fight continues for Ruiz's family. They said they don't know if he will be deported, but are exhausting any legal efforts to try to stop it.

His next court date is later this month.

Officials at U.S. Customs and Border Protection, who arrested Ruiz, and at U.S. Immigration and Customs Enforcement, which is currently holding him, did not answer questions about his arrest.