Do you need document to claim grandchild on taxes?

There are four items to be met:

1. Relationship - Are they related to you? Yes, as a grandchild.

2. Residency - They live with you more than 50% of the time.

3. Age - They are under 19 years old (or 24 if enrolled full time in school for at least 5 months) at the end of the year.

4. Support - They do not cover more than 50% of their own costs (working or investment income).