The death of a woman and her 15-year-old daughter's possible role in it have shone a spotlight on questions relating to Chinese parenting, marital breakdown and education. The girl, detained by police in Qingdao, Shandong province, on May 25, was the prime suspect in killing Zhang Yang, 45, a lawyer, who had been strangled on May 23 and whose body was found in a suitcase at her home that day, Beijing News quoted police investigating the homicide as saying.

The girl had said her mother was too strict with her, and this may have brought them into conflict, the paper quoted police as saying. The killing appeared to have been premeditated, they said. Shandong Chenggong Law Firm, for whom Zhang worked, said her funeral was held on May 28.

The girl's parents divorced when she was 3 years old and her mother had raised her alone since then. Media reports quoted workmates and neighbors as saying Zhang was a pleasant woman devoted to her daughter.

A poem circulated online said to have been written by Zhang described the girl as "the blue sadness in my heart", talked of the shortcomings of a broken family for a child, and expressed the desire to provide "extreme love".

In a society whose culture puts a high premium on filial piety, the woman's death and the background against which it happened have prompted some to suggest that the mental health of school students is being undermined by unhealthy parenting and an education system that puts excessive emphasis on academic performance and passing exams.

Matricide and patricide are rare in China, so when they do occur they tend to draw a lot of media attention. One of the most notorious cases in recent years was that of Wu Xieyu, a Peking University student suspected of murdering his widowed mother, Xie Tianqin, in Fuzhou, Fujian province, in 2015, when Wu was 21 years old. Wu, whose father had died of cancer in 2010, disappeared after his mother's death and was on the run until last year, when he was detained by police in Chongqing. He awaits trial.

Like the girl in the Qingdao case, Wu was regarded as a diligent student, and as in the case of Wang the allegedly killing of his father is said to have been premeditated.

Over the past decade the number of Chinese children living in single-parent families has risen greatly as divorce has become more prevalent.

The Ministry of Civil Affairs says that about 4.2 million couples ended their marriages last year, compared with just 1.1 million in 2002.

Psychologists, educators and parents say the growing number of divorces poses serious mental health issues for those in single-parent homes and underlines the need for good parenting.

Single parents often face greater pressure to balance financial and child-rearing obligations, the failure in this regard sometimes leading to inadequate parenting and social problems for both children and parents.

In the case of the Qingdao girl her mother would have tried to "offer the best education and expand her daughter's horizons", said Wang Qiang, a psychologist in Beijing. Zhang would have been trying, despite a failed marriage, to prove that she was a good mother, Wang said.

"As the girl grew up and became more independent in outlook there would have been increasing conflict between her and her mother. For Zhang, things her daughter wanted would have been unacceptable, and she would often have refused to give her things she wanted."

Zhang would have regarded independence as a threat to the girl's good upbringing, and at the age of 15 children more easily lose their temper or get angry with friends or families, Wang says.

"The girl may well have been confused, have felt helpless and have strongly resisted her mother's attempts to control her. On one hand she would have been aware what her mother was going through to raise her, but on the other, her self-esteem would have been growing and she would have felt the need for personal space, especially mentally."

The girl's emotional pain would have included anger toward someone who would not grant her what she sought and who could not even communicate properly with her, Wang says.

If the girl did indeed kill her mother, the violent denouement to this tragedy may have been an act of desperation, Wang says, the daughter seeing this as the only way out of the situation she found herself in.

He Rihui, the founder of the psychiatric Guangzhou Sun P&M Med Clinic, also speculated on the mother's role in the tragedy.

"She was a successful lawyer in a demanding job, in addition to her demanding family responsibilities."

In this environment, the girl may have felt under extreme stress and harbored anger toward her mother and had mental issues, He said.

From a psychological perspective, good child development requires the presence of two parents, Wang said. Single parents often must take on more hours at work to make ends meet, which can result in children feeling neglected and misbehaving.

Sigmund Freud, the founder of psychoanalysis, famously said that he could not "think of any need in childhood as strong as the need for a father's protection", which means children from broken homes need more attention and support to help them understand and recover from the upset or distress caused by their single-parent families, Wang said.

The Qingdao case is yet another reminder of the importance of parenting skills and support, she said.

Wang's death also raises questions about when the government should step in to have a say in parenting.

At the two sessions political meetings in Beijing in May one proposal that drew a lot of attention called for a license to be required by anyone wanting to have children. Under the proposal, couples would undergo parenthood training, and classes would be made available to help parents cope with the stress of raising children, particularly those with special need.

The last time that the issue of how hard parents should push their children was debated thoroughly in China was in 2011, when the book Battle Hymn of the Tiger Mother by the Chinese American Amy Chua was published. Notwithstanding the controversy over Chuan's no-holds-barred method in raising her two daughters, many parents in China enthusiastically adopted her approach, believing this would help them produce successful, high-powered young adults.

In November, the Ministry of Education suggested that as a way of alleviating pressure on young people, schools should reduce the number of exams and avoid making grades and rankings public. Such measures could help reduce academic stress and improve students' mental health, experts say.

However, Wang the psychologist says policy makers, schools, institutions, parents and doctors need to do much more on mental health issues.

About 30 million people under the age of 17 nationwide have emotional or behavioral disorders, and some of those have developed depression, the China Youth and Children Research Center says.

Early diagnosis and prompt intervention are crucial in reining in the progression of mental health issues, according to the center.

In December, 12 government bodies including the National Health Commission unveiled a plan aimed at curbing the increase in mental health issues among young people. Under the plan all schools in China could offer psychological services on campus by the end of 2022.

Such services would rely on on-campus facilities dedicated to mental health or on school doctors. Preschools and institutions receiving students with special needs would be required to be staffed by full-time or part-time mental health educators. Institutions for preschool education and special education would be required to have full-time or part-time mental health teachers on staff.