35. In order for an individual to claim the spousal tax credit for a non-resident spouse, or the dependant tax credit for a non-resident child or grandchild of the individual or the individual's spouse, it is necessary that such non-resident person be supported by or be dependent for support on the individual. The question of support or dependency is determined on the facts of each case. If the non-resident spouse, child or grandchild have enough income or assistance for a reasonable standard of living in the country in which they live, they are not considered to be supported by or be dependent for support on the individual. Also, gifts which merely enhance or supplement the already adequate lifestyle of the non-resident person do not constitute support.
http://www.cra-arc.gc.ca/E/pub/tp/it513r/it513r-e.html#P178_25861