Despite first responders’ efforts to revive her, she was later pronounced dead.
The other kids in the home, a brother and a sister, are now in the custody of the Department of Children and Families, family told WHDH-Channel 7.
Police remained outside the Wellington Street apartment building on Tuesday morning.
The girls was treated at the scene and transported to the hospital, where she died, police said.
Investigators are treating the little girl’s death as a “sudden death investigation”, according to the announcement, and there were “no signs of apparent trauma”.
A 2-year-old girl perished after the woman was also found unresponsive within a Worcester home on Monday, police said.
In a statement, a DCF spokeswoman confirmed that the agency had stepped in and taken custody of the other children.
In recent weeks Baker has found himself defending Lian Hogan, who was promoted to the second-in-command post at DCF this summer after overseeing the region that includes Worcester.