Castros say they knew nothing of Cleveland kidnappings. How is that possible?

Members of the Castro family say they saw signs that Ariel Castro was hiding a dark secret. But in dysfunctional families, people often don't ask questions 'because you don’t want to know the answer,' one expert says.

The brothers and children of Ariel Castro, speaking up now that he has been charged with kidnapping and raping three women whom he allegedly kept captive for a decade, are saying that they suspected he might be hiding a dark secret.

“All these weird things I noticed over the years about how he kept the house so locked tight in certain areas…. Everything is making sense now. It’s all adding up,” Angie Gregg, his daughter, told CNN Thursday.

Other family members have echoed these words, saying Mr. Castro kept multiple padlocks on most interior doors of his home, nailed windows shut, and prohibited guests from going upstairs or in the basement. He played loud music, presumably, they say, to drown out the noise of his captives. And Ricky Sanchez, a friend, told the Associated Press last week that Castro told him dogs were the source of the banging he heard from the other side of a wall. The door, Mr. Sanchez said, was secured with four or five padlocks.

Family members and friends have spoken to the press during the past week to express their sadness at what happened and to clear their names. In one poignant moment, Ariel’s daughter Arlene Castro appeared on “Good Morning America” and sobbed apologies to Gina DeJesus, a childhood friend and one of the women Castro allegedly held captive. Ariel Castro’s brothers, Pedro and Onil Castro, who were detained with Ariel but then cleared by police, took to CNN this weekend to plead their innocence.

In their stories, the image of Castro grows more troubling, and questions grow about how these signs could be seen only in hindsight. But family dynamics – particularly in dysfunctional families – can be built on denial, says Richard Moran, a criminologist at Mount Holyoke College in South Hadley, Mass.

“Dysfunctional families live with all kinds of secrets, and there are probably small differences – but significant ones – between what you feel to be going on, and actually knowing it for sure and having evidence,” he says.

“It is difficult to believe the rest of the family knew nothing of this, they must have had some kind of suspicion,” he adds. “However, a lot of times you may not ask questions because you don’t want to know the answer.”

Marie Caraballo, the daughter of Castro’s late ex-wife, told CNN's Anderson Cooper Thursday that she suspected something was wrong in the house after a visit several years ago when she was about 11.

“He told me ‘stay in the kitchen.’ I got a creepy feeling from him. Just the way he gave us a look,” she said.

Castro, who did not work after getting fired from his job as a school bus driver in September, appeared to want to always be close to home. He refused to travel out of state to visit relatives and often left family parties early to go home. Probably the strangest recollection many have of him is of a full-size mannequin Castro groomed to look like a woman; he kept it in the house to scare others from wandering inside.

By contrast, Castro freely showed off the 6-year-old daughter he had with Amanda Berry, one of the three women freed form his Cleveland house. He often took the girl to a local park, and in her CNN interview, Ms. Gregg said he once showed her a cellphone picture of the girl and said it was his girlfriend’s baby. But Gregg said she had her suspicions when she noticed the girl resembled her sister.

Castro is currently being held on $8 million bail. He was arrested alongside his two brothers. But police said they were not involved, and since being released both brothers have said they had no knowledge of the alleged kidnappings or rapes – and would have called law enforcement immediately had they known.

“There’s no reason for anybody to think that I would ever do something like that,” Onil Castro told CNN.

“If I knew my brother was doing this … I would call the cops because that ain’t right,” added Pedro Castro in the CNN interview. “People are going to think, ‘Pedro’s got something to do with this,’ and Pedro don’t have nothing to do with this. If I knew, I would have reported it, brother or no brother.”

What was known before last Monday was Castro’s history of domestic violence against Grimilda Figueroa, his wife. According to the Associated Press, he was accused of severely beating Ms. Figueroa, causing severe injuries. During their time together, he padlocked the front door from the outside, preventing her from leaving when he left, and refused her access to the phone.

Figueroa filed a domestic violence complaint in 2005 after she said Castro threatened to kill her and her children, but records show her case was dropped because her attorney did not appear at a hearing. It was the third time he was in court: In 1989 he pleaded no contest following a domestic violence complaint and was given a year of probation. In 1993, Castro was arrested and charged with domestic violence against his wife, but the case was dropped after Figueroa declined to offer details of the abuse. She was granted full custody of her children in 1997.

Figueroa died last year.

In interviews, family members have said they feared the negative impact against their family. Castro’s mother and brothers have gone into hiding and Gregg says she wants the world to know that her father’s actions “are not a reflection” of her family.

“We don’t have monster in our blood,” she told CNN.