My girlfriend and her two kids are living with me and I support them for everything. What are the requirements for me for filing my taxes? Am I allowed to claim them as my dependents even though they are not my children and she doesn't collect any child support from their fathers? Would it be considered head of household or still single?
Plus she recently started working, does she have to file taxes? If so, can she claim the child tax credits? If only one of us is allowed to claim them, who would benefit more? What are the requirments and limitations for her filing?

Thanks!