Carrie thought she was ready to go back to work four weeks after the death of Siobhán, the daughter she and her husband lost to brain cancer at seven months old. But, in reality, she wasn’t. “I really struggled to cope,” she says. “I was a teacher and there was nowhere to hide: I had to deal with children, parents and colleagues all day, every day. There was no downtime and no office for me to retreat to.”

Returning to work just added to her trauma. “I had to put on a false face, which was exhausting. All sorts of things triggered my grief during the day, but I had to bottle everything up,” she says. “I had to contain and condense my grief into predetermined time slots when I was at home. As a parent who has lost a child, you never stop grieving, but I don’t think that was good for me in the short or long term.”

The new legislation, Jack’s law, is said to be the most generous parental bereavement pay offer in the world: it will give all working parents who suffer the loss of a child two weeks of statutory paid leave. But while welcoming the official recognition that bereaved parents need to grieve, Carrie is worried about the two-week time frame: although it offers a cushion for the immediate loss, not only is two weeks not nearly long enough, it might even backfire.

“I’m concerned that these two weeks will be seen as the official and ‘correct’ amount of time that people need to get over their loss,” she says. “It is of some help, but it is only a start. Nobody can complete their grieving within two weeks. Parents will still be arranging a funeral to begin with and it is only after that they can begin to grieve. While I appreciate the cost of providing any leave, further support needs to be available once parents return to work, much as it is on return from illness.”

The new law, which is expected to come into force in April, is the culmination of a decade-long campaign by Lucy Herd, whose 23-month-old son, Jack, drowned in a pond in 2010. At the time of his son’s death, Jack’s father was allowed only three days off work to grieve, one of which had to be for the funeral.

“In the immediate aftermath of a child dying, parents have to cope with their own loss, the grief of their wider family, including other children, as well as a vast amount of administrative paperwork and other arrangements,” says Herd. “A sudden or accidental death may require a postmortem or inquest, and there are many other organisations to contact, from schools to benefit offices.”

Until now, there has been no legislation covering how much leave companies must offer when an employee’s child has died: the law simply said that the amount should be “reasonable”.

On its website, the Advisory, Conciliation and Arbitration Service (Acas) advises employers to “be compassionate towards a person’s individual situation; remember that everyone deals with bereavement differently (some people may need more time off than others)”. But in advice that will shortly be out of date, it reminds employers: “There is no automatic right to paid time off for bereavement.”

The Rainbow Trust, which supports families with a seriously ill child from diagnosis through to bereavement, was part of the consultation process behind the new law. Anne Harris, Director of Care at the charity, says that, while she welcomes it, she “would caution that it should not be assumed that grief can be resolved in two weeks. Parents tell us that they never get over the death of their child, they just learn to live with it.

“When parents return to work, we would encourage employers to have a conversation with them to agree the approach they would like, and encourage line managers not to shy away from these important, albeit difficult, conversations,” she adds.

Small-scale research by the Rainbow Trust in 2014 found that more than half of the 58 bereaved parents who took part in the survey did not feel their employers gave them enough time to cope.

The study also found that one in three bereaved parents felt that their employers put pressure on them to come back to work after the death of their child. Ten of the respondents said they had left their job because of the way they were dealt with during their bereavement.

Half the parents surveyed took at least one month off work, with more than a third feeling that four months or more would have been ideal.

Paul’s daughter died at six weeks old from epilepsy and encephalopathy. He says that, in his case, no amount of leave could have helped; that he was only just starting to function again after the six months’ full pay and six months’ half-pay his company gave him. “If I had gone back two weeks after, it would have been very difficult,” he says. “I was very, very angry. I stayed angry for about three months and became a recluse. My wife was in shock. Being pregnant for nine months and not bringing your baby home is something that I could never understand or relate to. So we were on two very different pages.

“If I had taken this grief into work with me after two weeks and left my wife at home, it’s really difficult to understand how that would have worked out. My initial thought is that it would have been awful. To have the spotlight on me like that after such a short period of time, in which I did not have time to process what had happened: I can’t imagine how I would have dealt with that.”

On the other hand, he says, the acknowledgement that parents need to grieve that comes with Jack’s law is helpful. “Time is the biggest thing when you lose your child,” he says. “Grieving hurts and it takes time to process what has happened. My brain would not let me think about what we had been through for a few days. Every time I thought about the child I had lost, my mind just played music to distract me and I lost my train of thought. It was very weird.”

Jack’s law, which will help 10,000 bereaved families in the UK every year, will cover all working parents who lose a child under the age of 18 or have a stillbirth from 24 weeks of pregnancy, irrespective of how long an individual has been with their employer. In a move that has been particularly welcomed by campaigners, the two weeks’ leave can be taken either in one block or in two separate blocks until the first anniversary of the child’s death.

Kiran Daurka, an employment law partner at Leigh Day, says that while two weeks is not long enough for parents to grieve: “The main plus of this law is that fathers now know they have a right to ask for leave. Fathers often feel put to one side, with all the sympathy going to the mother.”

Daurka adds that she hopes employers will treat this two-week period as a bare minimum for grieving parents. “Now companies know that parents have the right to leave and that they can claim those two weeks’ statutory pay back from the government, I hope employers will be more generous because they can now afford to offer more on top of those two weeks.”

She would also like the new law to generate helpful conversations in companies that have not previously thought about this subject. “The whole issue of compassionate leave is very unclear, with it really being at the discretion of companies, who often make it up as they go along,” she says. “Child bereavement is so unusual that companies often haven’t even thought about it.”

For those who have miscarriages, the new law will not apply. Rebecca, 46, was not allowed any bereavement leave after a traumatic miscarriage when she was 10 weeks pregnant. And yet, she says: “The trauma of going through a miscarriage is a physical and emotional pain I wouldn’t wish on the most evil person. It’s agony. Utter, physical agony. Coupled with the emotional and mental trauma, miscarriage is devastatingly overlooked in terms of child loss, unless you have experienced it for yourself.”

Rebecca was only allowed sick leave, “so it went down on my HR records that I had had a miscarriage”, she says. She started miscarrying at work. “It was the most traumatic experience I have had,” she says. “No one at work knew that I was even pregnant yet, so I had to inform my manager I was pregnant and losing the baby all in one go. I couldn’t get myself to A&E as the bleeding was so fierce and the pain excruciating.

“I had two days off, the Thursday and Friday, and then the weekend. I was in shock. I was embarrassed. I was hurt that no one from work seemed to care. The week prior, a colleague had been involved in a car accident. She was fine, just a little shaken. She had four days off work and the office sent her a card and flowers. I didn’t even get a phone call and when I returned to the office, no one asked how I was,” she says.

The cut-off age of 18 also strikes many as unjust. Max’s newly married daughter died suddenly last year, two weeks after her 26th birthday. Like Herd’s husband, Max was given only three days’ paid leave. He took the day of his daughter’s death off, but was back at his desk on Monday morning, needing the other two days for her funeral – which didn’t take place for seven weeks because the family needed to wait for the coroner’s report.

“The pain is so acute, so physical, that I wondered sometimes how I could continue to breathe in and out. Sleep patterns are shot to pieces. You don’t think about food until someone puts it in front of you.

“After two weeks, it’s easier. You can function. The paperwork is almost done. Sleep is settling. You get a feeling that it might, eventually, be OK,” Max says. But he was still far from ready to return to work: “It is now almost a year, which brings its own issues.”

Max is critical of the fact that Jack’s law comes with an age limit. “I feel disappointed and slightly distressed that it is only for parents of children under 18,” he says. “My daughter may have been an adult, but was no less my child and I am insulted to think that my grief is somehow less worthy than that of a parent who has lost a child under 18.”

Chris Parker wonders if there is anything that employers can do to help when dealing with such a deep level of grief and trauma. His 19-year-old daughter, Laurel, had a life-limiting condition and died in 2015. Parker stopped work when the doctors said she was close to death and says his employers were exemplary. They gave him as much time off as he needed and, after her death, organised a collection for the child’s hospice. Colleagues sent supportive messages while he was off work and were sympathetic when he returned.

At the deepest level, however, it did not change anything. “As a parent, having a child die is a life-changing experience, affecting mental and physical health for many years,” Chris says. “Nearly five years on, I still don’t feel like the employee I was before Laurel died.

“I will never be as happy as I was when Laurel was alive and that greatly affects me in and out of work. No amount of leave, holiday or joyful experiences makes good the gap in my life.”

Some names have been changed

• The subheading of this article was amended on 3 February 2020 to more accurately reflect the contents of the article.