(NC) -- When your child wakes up feeling out of sorts, you trust yourself to know the difference between a bad day and the latest bug sweeping the school. You're drawing on a lifetime of learning from other parents, relatives, friends and the media, plus intimate knowledge of your child.

But it's not so easy to distinguish a possible mental illness from the normal ups and downs of growing up. Suppose your child has trouble making friends. Is he just shy, or could he be suffering from anxiety, the most commonly diagnosed mental illness in young people?

Early intervention can head off needless pain and equip a young person with coping skills that last for a lifetime. But fewer than 10 per cent of kids who need specialized treatment are actually getting it.

According to the 2012 RBCChildren's Mental Health Parents Poll, many of us take a 'wait and see' approach with signs of mental illness. Kelly Hrudey, a former NHL goaltender, has a daughter diagnosed with anxiety disorder – and like 67% of Canadian parents surveyed in the RBC poll Hrudey didn't know when to take action.

"We noticed changes in our daughter's behaviour but chalked it up to a 'stage'”, he explained. “I wish I had known the warning signs to look for, so we could have recognized the problem earlier.”

With physical illnesses, you have parental instinct on your side. Mental illness can be harder for parents to determine. Hrudey stresses the importance of knowing the early warning signs of mental illness. Here are five common early warning signs that parents tend to wait before acting on:

• Mood changes/swings: Persistent sadness or withdrawal;

• Anxiety: Frequent, prolonged worrying;

• Sudden change in grades: Poor concentration can lead to anxiety about going to school or a change in classroom success;

• Heightened emotions: Exaggerated fear or anger for seemingly no reason;

• Behavioural changes or acting out: Out-of-character changes in behavior or personality.

RBC supports a wide-range of programs that help children and youth stay happy and healthy, inside and out. An initiative called the RBC Children's Mental Health Project funds organizations across Canada to provide trusted resources and programs for parents. More information can be found at www.rbc.com/childrensmentalhealth.

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