If all of you have lived together for the entire year of 2019, AND you are not claiming your own children (did you not have any income?) then BF *might* be able to claim the children as "qualifying relatives" even though they are not related to him. He cannot use them to file as HOH or to get the child tax credit or earned income credit. He can get the $500 credit for other dependents for them.
CREDIT FOR OTHER DEPENDENTS
https://ttlc.intuit.com/questions/4499708-what-is-the-500-credit-for-other-dependents-family-tax-cre...
IRS interview to help determine who can be claimed:
https://www.irs.gov/help/ita/who-can-i-claim-as-a-dependent
**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.**
