The short answer is "yes." The long answer depends on a bunch of details -- is he on the birth certificate? Where, exactly, does everyone live? Does the father have any income or resources? You (or more precisely, your niece) should consult with a family law specialist in the state where the man lives to determine whether and how to file a custody/support case.
Answered on Feb 19th, 2021 at 6:30 PM