The doctor says there's nothing wrong. You don't want to disagree with the expert.
But your mother's instinct is telling you that something really isn't right with your child.
Should you ignore that nagging feeling that your child 'just isn't himself' – or should you go with your gut and risk being branded a 'fussy' parent?
In a recent tragic case, Linda Peanburg King's seven-week-old baby Axel died of pneumonia after several visits to her local out-of-hours centre in North London.
She told the inquest into his death that after being sent away with antibiotics, she brought him back because 'my gut feeling was taking over.'
Perhaps we should all trust our parental instincts more. In fact, medical experts say that they're a vital part of getting the right diagnosis for a child.
"When a parent feels that something isn't right, from a paediatric perspective I ignore that at my peril," says Dr Alison Bedford Russell, neonatal consultant at the Warwick Medical School, Birmingham.
Take Michelle, a first-time mum. She 'just knew' that something was wrong with her baby, Oliver, even though he was only a few hours old.
"He was grunting and he was freezing cold. He just didn't feel right," she says. "He wouldn't feed, bottle or breast. I told the midwife over and over again. I begged her to look at him properly. But she just thought I was being finicky.
"I asked to see a doctor and was told no, Oliver was just tired. When he did turn up, he said there was nothing wrong with Oliver and I should just try doing skin to skin. I'd already done that. So he said he'd have a look at Oliver 'just to put my mind at ease.'"
At that point the doctor noticed that Oliver was jaundiced and took some blood. Within a few hours, two doctors and a midwife arrived to take Oliver to the special care baby unit straight away. He had Group B Strep – a bacterial infection which can kill – and was extremely ill.
Thankfully, Oliver recovered after a week in hospital. "But if I hadn't made the doctor take him, I don't think he'd be with us now," Michelle says.
Mother's instinct doesn't just kick in with very young children, either. When seven-year-old Sara started complaining of headaches and noises 'banging in her head', doctors told mum Ewa that her daughter was just adjusting to a new climate after the family moved to a different country. But Ewa knew better.
"The way she was sleeping, breathing, smelling – it was all strange," she remembers. "I kept telling them that she needed a blood test. When they eventually checked her blood, they called me the same day to tell me that I had to rush her back into hospital."
Sara had acute myelogenous leukaemia (AML), a form of blood cancer. She survived thanks to a cord blood transplant – and Ewa's instinct.
Joanne Hughes started her support group, Mothers' Instinct after her daughter Jasmine died from a rare neurological disorder, acute disseminated encephalomyelitis (ADEM). She was just 20 months old.
"Parents know when their child is not herself," she says. "They know what is 'normal' for their child. Assessing shouldn't be a tick-box exercise.
"My concerns were not taken seriously. We were sent home countless times. Jasmine was not given essential scans and tests urgently. It took nearly three weeks. Once the results of these tests came through, she was given treatment for ADEM – but they had not done those tests quickly enough."
And Joanne wants Mothers' Instinct to work with medical professionals in raising awareness of how vital this intuition can be.
"They have to understand that they can miss things," she says.
Bedford Russell agrees: "Of course, there are some parents who are desperately anxious about everything. But becoming a parent is really an anxiety-provoking event! Even as a paediatrician, I am always worried when my children got ill. The fact is, parents can't and shouldn't be fobbed off. If your baby isn't right, keep going. Seek help. Get the help that your baby needs."
Ways to use your intuition wisely
Video your child's symptoms using your smartphone in case your child suddenly recovers in the waiting room.
Ask what the doctor has written down about your child. Sometimes they miss out something they feel isn't important but turns out to be significant. For example, doctors often listen out for stock symptoms, like 'headache'. But a toddler might not be able to tell you that she's got a headache, so you might not know. Instead, you might say that she's irritable or sleepy.
Don't be afraid to ask how much paediatric experience a doctor has, or for a second opinion.
Trust yourself. If you're wrong and your baby is fine after all, that's a great outcome – but it's best to be sure.
Don't worry that being persistent will affect your baby's care adversely. It's more likely that it'll get your child the treatment he needs.
For more information on cord blood transplants, visit the Anthony Nolan Trust.
The charity Group B Strep Support wants all pregnant mums to be routinely tested for the bacteria. To sign the petition, click here.