Children who have experienced the death of a loved one could be more likely to struggle with psychosis.

A family death has been linked to a "small but significant" increase in psychosis in children, a British Medical Journal (BMJ) news release reported.

The risk is believed to be a higher in children who have had a member of their "nuclear family" (siblings or parents) commit suicide.

Past studies have linked adult mental illnesses with "genetics, lifestyle and environmental experiences." Psychological stress during pregnancy has also been linked to disturbances if fetal development.

Very little research has been conducted that looked at a link between maternal stress and psychosis in the offspring.

In the recent study, a research team analyzed the link between "deaths in the family as a form of severe stress to the individual and subsequent psychosis," the news release reported.

Their definition of psychosis included conditions such as schizophrenia as well as affective psychosis including "bipolar disorder with psychosis and unipolar depression with psychosis."

The team categorized exposure periods into: "any exposure" (meaning at any time pre or post-natal); "any prenatal"; "any and postnatal" (up to the age of 13). They also classified exposure into trimesters and age groups  (zero to 2.9 years; three to 6.9 years and seven to 12.9 years).

About 0.4 percent (1,323 study subjects) of the entire study pool developed non-affective psychosis and 0.17 percent (556 subjects) developed an effective psychosis. Out of the entire study 11,117 children were exposed to death from suicide, 15,189 were accident-related, and 280,172 experienced death as a result of "natural causes."

The team did not find a link between prenatal exposure and psychosis risk.

"An increased risk of 'all psychosis' was associated with deaths in the nuclear family and risk increased the earlier in childhood the death occurred," the news release reported.

Exposure to suicide was linked to the highest risk of psychosis followed by accidents and then death from natural causes. The highest risk occurred in the zero to three age group.

"Our research shows childhood exposure to death of a parent or sibling is associated with excess risk of developing a psychotic illness later in life. This is particularly associated with early childhood exposure. Further investigation is now required and future studies should consider "the broader contexts of parental suicide and parental loss in non-western, ethnically diverse populations," Professor Kathryn Abel, from the Centre for Women's Mental Health at The University of Manchester, said in the news release.