A dependant is a person, especially a family member, who relies on you for financial support. We are sorry to hear about your son's mental struggles in daily life. However, the CRA's requirement is that the disability must affect the person's ability to interfere with their basic functions such as feeding, dressing, vision, etc.
If you want, you can try finding a psychiatrist to fill out the part B of form T2201 Disability Tax credit.
If you require further assistance please contact our phone support team or contact us directly on Facebook or Twitter.
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