First came the bad dreams.

Within days of witnessing her mother's death, the 2-year-old girl stopped sleeping, her relatives say. She then started having flashbacks to that night and hallucinated that she had blood on her hands that she couldn't wash off.

The girl had been staying with relatives since her 27-year-old mother, Raven Gant, was shot and killed Thanksgiving night in an apparent domestic dispute with the toddler's father. Randall Watkins, 41, was arrested at the scene and has since been charged with murder.

Many children who experience trauma go on to lead relatively normal lives. But in others, trauma increases the risk of depression and substance abuse and can lead to more aggressive behaviors in adulthood, research shows.

The toddler's behavior didn't surprise Abigail Gewirtz, a University of Minnesota family social science professor, whose research has found that kids also cope in ways that don't always make sense to observers.

"Sometimes, they see kids who've just lost a parent running and jumping and cycling and watching TV, and they think, like, 'Don't they care that they lost their mother?' " said Gewirtz, who serves as director of the U's Institute for Translational Research in Children's Mental Health. "Well they do, they just grieve in a different way."

Court records show that when a social worker interviewed the girl on Dec. 2, she showed no outward signs of stress.

"She had her hair nicely braided and was wearing clean, weather-appropriate clothing," the records said. "She appeared content with her environment and seemed connected to several family members at the home."

When police responded to Watkins' apartment in the 2600 block of N. James Avenue on the night of the killing, they found Gant lying on her back with a gunshot wound to the left shoulder, according to court filings. The girl was standing in the dining room, and when asked by officers where her mother was, she replied, "She's on the floor," the filings say.

The Star Tribune is not naming the girl to protect her identity.

The question of why some kids are more resilient than others continues to stump researchers.

Research shows that trauma can affect kids as young as 18 months, according to Jillian Turanovic, an assistant professor of criminal justice at Florida State University who has studied the effects of trauma on children. Even witnessing an act of violence can be "almost as devastating as if they were directly victimized," she said.

"For kids, their brains are still very much developing, so experiencing trauma, especially in those early childhood years, it can affect brain development and affect feelings of safety," Turanovic said. "It can kind of snowball and manifest."

Another problem, she said, is that access to mental health and counseling is extremely limited in neighborhoods where violent crime is commonplace.

"So people who are most likely to be exposed to gun violence are also the people who are least likely to have access to those resources that can help them recover," she said.

In the case of the 2-year-old girl, the city of Minneapolis has agreed to cover the costs of therapy until funding from the state Crime Victims Reparations Board kicks in.

The effects of trauma, from domestic violence to natural disasters like hurricanes, on children are well documented.

A 2011 study by the Minnesota Department of Health surveyed 17,000 adults and found that more than half had at least one serious traumatic experience as children, or adverse childhood experiences (ACEs). These include physical or sexual abuse, or living in the same household as someone who has struggled with mental illness or substance abuse or has been incarcerated, the study's authors said.

"ACEs also tend to occur together, meaning that those Minnesotans reporting one ACE are more likely to report other ACEs," read the study.

Children respond to trauma differently.

Martha Timberlake's daughter Jayda, then 5, was struck in the foot by a stray bullet that sailed into her North Side home in August when a gunman opened fire on a man who lived in the duplex above her. She says she was told that the experience would likely have lasting psychological repercussions, but so far she hasn't noticed a change in her daughter.

"Before we left the hospital, she saw a psychologist and they said that she seems fine and they don't think she needs any further help, until I see changes in her behavior," she said. "She's being everybody's strength."

Study after study has found strong evidence showing that childhood exposure to violence, whether as victims or witnesses, can increase the likelihood of abusing drugs or alcohol, suffering from anxiety, or engaging in criminal behavior and being drawn into a cycle of violence.

Less is known about why some people are eventually able to steer clear of such hazards.

Children exposed to frightening or threatening events are likely to develop toxic stress, which can impair brain development while ratcheting up fight-or-flight hormones — the body's physical response to a challenge, according to Resmaa Menakem, a Twin Cities-based social worker and national expert on cultural trauma.

"When we're talking about trauma, the nervous system doesn't come down; it stays stuck and that's where hypervigilance comes in play — that's where her washing her hands, thinking she has blood on her hands, comes into play," said Menakem, adding that trauma can have other long-term devastating effects. "This little girl just lost two parents: she didn't just lose her mom, she has now lost her dad for all intents and purposes, and a lot of times we don't account for that grief."

Libor Jany • 612-673-4064 Twitter: @StribJany