My mom get social security I pay her 5,200 a year to take care of my kids if I claim this on tax return will that affect her? She does not file a tax return

[DianeW777]

Yes.  If you are paying her to take care of your children then she must report this as self employment income, or you might be considered her employer if she does it in your home.  

She will have self employment taxes on this income but it's not likely her social security will become taxable unless she is married and files jointly with her spouse.

If it is a gift from you to her there is nothing to report for either of you. This would mean you would not be entitled to the child care credit.

[Hal_Al]

Q. if I claim the dependent care credit (DCC), on my tax return, will that affect her?

A. Maybe.  

If you claim a tax benefit (e.g. DCC), then she must claim the income. But, it may still not be enough to trigger a tax liability.  It depends on whether, she baby sits in you home or hers.  if she sits in your home, she is a household employee, and as a grandparent, exempt from social security and Medicare tax.  If the $5200 is her only income, other than social security, she will pay no tax.  But, she should file, so her income matches your deduction (actually, tax credit). 

If she sits in her home, she may be considered self employed and subject to  security and Medicare tax (reported as " security and Medicare tax", about 15% of the $5200).   Some, in this forum, argue that it can be reported as hobby income and not subject to  security and Medicare tax.