One piece of advice you could offer the "taxpayer" this is about is to become legally married to his GF. Then he could file a joint return, get the married filing jointly standard deduction, and they could claim the grandchild as a dependent on their joint return and get the child-related credits.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
