Abdominal pain and discomfort are common complaints in young children.
However, for a small number of children, these symptoms are the sign of a hernia or appendicitis.
Indeed, hernia repair and appendix removal are among the most common types of surgery performed on children.
So what causes these conditions and when should you seek help?
The simple definition of a hernia is a soft lump under the skin. It occurs when tissue bulges through a weak spot - or small opening - in the groin muscles to create a ‘lump.’
According to Paediatric Surgeon Joe Curry, the exact cause of hernias is unknown, although some infants are more prone to them than others.
“They’re more common in children who were born prematurely, especially those more than eight weeks premature,”
says Mr Curry who works at The Portland Hospital and Great Ormond Street Hospital.
“Children who have a family history of hernias are more susceptible, and boys are more likely to develop them than girls.”
The usual sign for parents to look out for is a swelling that appears in the groin.
The good news, says Mr Curry, is that this swelling is usually ‘intermittent, will mostly go away by itself and usually doesn’t produce any significant pain or discomfort’.
However, it is sensible for parents to point out this swelling to their health visitor or GP, he advises.
He adds: “Because of its intermittent nature, it can be very useful if mum or dad takes a picture of the swelling on their camera phone to show to the GP or health visitor.”
If surgery is necessary, the treatment is very safe and straightforward and, for the vast majority, provides a lifelong cure.
However, in a small number of cases, hernias can require urgent medical treatment.
This is when the intestine (in a boy) or the ovary (in a girl) becomes trapped inside the hernia causing the area over and around the lump to become very painful and tender.
Mr Curry says: “If the intestine is trapped then this will block the intestine, producing swelling of the tummy and green vomiting. If parents are concerned about any of these symptoms, they should take their child immediately to the nearest children’s casualty department.”
Unlike most hernias, a swollen appendix often causes severe pain in children.
The appendix is a worm-shaped pouch which usually sits in the lower right hand part of the abdomen.
No-one really knows what causes appendicitis, says Kate Cross, a Consultant Neonatal and Paediatric Surgeon at The Portland Hospital and Great Ormond Street Hospital, although it affects around one in every 15 people.
“It (the appendix) probably gets blocked with something like a bit of poo and then becomes swollen and infection can occur,” explains Miss Cross. “It typically occurs between the ages of 5 and 40 years.”
The key warning sign is tummy pain that starts in the middle of the abdomen and then moves to the right lower side.
The pain may start gradually but, as the appendicitis becomes worse, so will the pain.
Appendicitis is treated with a combination of antibiotics and an operation to remove the appendix, usually using keyhole surgery.
There are cases when a child needs urgent treatment, for example, if an appendix bursts and the infection spreads inside the tummy. The main symptom of a burst appendix is severe pain, especially with movement.
Distinguishing between appendicitis and gastroenteritis can be difficult.
A temperature, nausea and vomiting can occur with both conditions, so a doctor may need to carry out repeat examinations.
Miss Cross advises to always see a GP if you are concerned, especially if your child’s pain becomes worse or is severe.