One aspect of this matter that is not mentioned. Sally could employ her son to work for her. He would earn an employment income subject to normal taxes while Sally's business would get an employment expense deduction.

He would have to pay some taxes on this income but has access to basic non refundable deductions that would shelter most of it from taxes.

On the plus side, too, he would build RRSP contribution room, contribute to EI and CPP which have long term income stability  benefits.

Sally and her ilk are focusing too much on reducing taxes and not enough on bigger picture issues.