A parent's role is not necessarily to eliminate the anxiety, but help to manage it, according to Cognitive Behavioural Therapist Claudia Prothero.
Prothero, who specialises in childhood anxiety disorders, said whether a child has been officially diagnosed with anxiety or not, the way a parent can help doesn't change.
"We have seen very high numbers of children coming for treatment over the last five years, and this seems to be increasing," she told The Huffington Post UK.
"Parents can really do a lot at home to help a child suffering with anxiety."
If you've noticed your child experiencing anxiety, Emma Saddleton, parents helpline manager at YoungMinds, wants parents to be reassured they're not alone.
“All children and young people get anxious at times, and this is a normal part of their development as they grow up," she said.
"Some children are just naturally more anxious than others, and are quicker to get stressed or worried."
Saddleton said parents should only be concerned if they feel their child's anxiety is having a significant effect on their school or relationships.
“Many children and young people don’t know what they are feeling when they are anxious, and it can be very frightening and overwhelming," she said.
We chatted to three parents whose children frequently experience anxiety, but have not been officially diagnosed.
Spotting signs of anxiety in your child
"My son is nearly eight, and I first noticed his anxiety when he was four and a half," said Jordan Martin, 35, whose son experiences increased anxiety before school and before bed, told HuffPost UK.
"I had to take him to school despite the signs of anxiety, which were out of character: crying, shaking and tummy nerves," she explained.
"I would drop him off at school and cry when I got home… It was so important that I was consistent in him attending, but I felt awful."
Martin said other signs of anxiety included her son talking before bedtime about "bad stuff" that might happen.
"He was worried about silly things like his school bag not being at home, anything that related to change," she added.
Mum Salma Shah, whose five-year-old daughter frequently experiences anxious thoughts, said it's been consistent since she was a baby.
"As a baby, I remember her turning her back to all the other babies to face me and distract me by pointing at things," Shah explained.
"One of the main symptoms I noticed when she grew up was her clinging on.
"If she had a playdate, she would just be by my side and would never voluntarily talk to people, not even family members she has known all her life."
Natasha Jones, 35, said her seven-year-old daughter Ella's anxiety stemmed from getting upset when thinking about illness and death in the family.
It was reinforced the first time she watched Harry Potter and Cinderella. These films caused her to worry about death and losing her parents.
"She became constantly worried about being on her own when at home or with someone else in her family," Jones explained.
"The problem was definitely at its worse if I was not around at home.
"It affected her concentration on things like homework or play and she got very emotional before bedtime, with stomach ache a common occurrence."
How can you help manage a child's anxiety?
1. Break down situations into small chunks.
Prothero said when a child is feeling anxious about a scenario, it is tempting to help them avoid it. But this means they'll never develop confidence.
"Instead, help them break down the situation they are struggling with into smaller chunks and give lots of praise and rewards when they face each chunk before stepping up to the next level," she explained.
"For example if a child is socially anxious, encourage them to attend small gatherings and let them get used to that before trying a slightly bigger party."
2. Use guided relaxation techniques.
Martin creates a "safe place" for her son where he can feel protected and calm before he goes to bed. She speaks to him using guided relaxation techniques, such as a soft tone and positive phrases.
"The words parents can say during this relaxation are best catered to their child’s needs," she said. "I use first person, which works well, for example saying: 'Repeat in your mind, ‘I am safe, I am home where ever I am, everything is fine.'
"A soft tone, with a light touch on the shoulder or on the upper chest works well.
"Be mindful not to used negative words, so instead of saying: 'You don’t need to be scared', say something like: 'You are safe, all is calm, and everything is fine'."
3. Educate them about breathing techniques.
Breathing, in general, helps anyone who is feeling anxious bring their attention to the action of breathing rather than what's worrying them. Controlling this can create a sense of calm and prevent future anxiety attacks.
Martin said she uses these techniques to calm her son.
"I use the technique of inhaling through the nose for a count of four and then exhaling through the nose for a count of four," she said.
"The aim is to give children back control over their emotions, so if they reach a ‘scary’ or ‘uncomfortable’ situation they have safe and effective strategies to call upon, like the powers of a superhero."
4. Initiate a "happy thought".
Martin says she tries to give her son a positive affirmation each night before sleeping and each morning before school - when he feels his most anxious.
"He specifically asks for it now," she said. "I think he feels secure and supported knowing he can focus on this while going to sleep, or walking into school.
"My husband initiated ‘the happy thought’. My son will ask: 'What’s my happy thought?'.
"We encourage him to choose his own happy memory, because it is his mind and only he can know what lifts his spirits."
5. Prepare for situations that provoke anxiety.
"We get to places or parties early so my daughter isn't walking into big crowds," Shah said, explaining her daughter suffers from social anxiety.
She said preparing for potentially anxious situations in advance enables her daughter to manage it better.
"She responds well to gentle nurturing," she added. "We also praise her highly when she does join in at a party or event to build on her success."
6. Over time, expose your child to different circumstances.
Shah said parents should never worry about the potential embarrassment of their child being "too clingy".
They should focus more on building their child's confidence.
"Don't push them too hard," she advised.
"But gently, over time, expose them to different circumstances that take them out their comfort zone."
7. Don't be angry, work as a team.
"We try to be understanding and recognise my daughter's issues," Jones explained.
"We did lots of research to try techniques that suited Ella and one of the best ways to reassure her is to talk to her.
"Telling her that she is not alone and other children have the same fears, including me, is reassuring.
"We work as a team and she knows it will take time for her fear to disappear."
8. Create a 'worry' book.
Saddleton said to help children with anxiety in the longer term, creating a worry book can encourage them to notice what things make them anxious - their triggers.
"Only if they are old enough to do this, get them to write their thoughts down in a 'worry book'," she added.
Jones said her daughter uses this technique, writing her thoughts down in a "worry box".
9. Speak to other parents.
For parents struggling to know how to help their child deal with anxiety or anxious thoughts, Jones said speaking to other parents to hear their techniques may give you ideas.
10. Seek help from a GP if anxiety persists.
"If the anxiety is not improving over two or three months or is significantly impairing your child's ability to socialise or attend school you should seek professional help," Prothero advised.
"Therapists specialising in children can be access privately or through your GP.
"The government recommend that children with social anxiety should have 8-12 sessions of Cognitive Behaviour Therapy."