Copied from CRA website.
Are you eligible for the caregiver amount?
If, at any time of the year, you (either alone or with another person) maintained a dwelling where you and an eligible dependant lived, you may be able to claim this amount. The dependant must have been one of the following individuals:
your or your spouse or common-law partner's child or grandchild; or
your or your spouse or common-law partner's brother, sister, niece, nephew, aunt, uncle, parent, or grandparent who was resident in Canada.
In addition, your dependant must have met all of the following conditions. The person must have:
been 18 or over at the time he or she lived with you;
had a net income of less than $16,705 (line 236 of his or her return, or what line 236 would be if he or she filed a return); and
been dependent on you due to mental or physical infirmity or, if he or she is your or your spouse or common-law partner's parent or grandparent, born in 1939 or earlier.
You cannot claim this amount for a person who was only visiting you.
If you were required to make support payments for a child, you cannot claim an amount on line 315 for that child. However, if you were separated from your spouse or common-law partner for only part of 2004 due to a breakdown in your relationship, you can still claim an amount for that child on line 315 (plus any allowable amounts on line 305 and line 318) as long as you do not claim any support amounts paid to your spouse or common-law partner on line 220. You may claim whichever is better for you.