A callous Boston mom allegedly told first responders her four-year-old daughter was “drinking milk when she turned blue” – as the little girl was dying of fentanyl poisoning, prosecutors revealed in court Monday.

Dayanna Familia, 35, was arraigned in Dorchester after police arrested her on Saturday for the Aug. 17 death of her daughter Liyanna, NBC 10 reported. 

The tot’s tragic death unfolded in the 200 block of Fuller Street just before 9 p.m. in August, where officers tried to save the little one, who died after being rushed to a local hospital, Boston police said. 

In court Monday, officials said that Liyanna died from unknowingly ingesting fentanyl, which Familia declined to report to authorities at the time.

Prosecutors alleged that the maniacal mom then concocted a tale about what caused her daughter’s medical episode. 

She told EMS personnel, who were in the midst of trying to save the girl’s life, that “the child was drinking milk when she turned blue and perhaps had gotten into a roach trap” – even though she likely knew the illness was caused by the deadly drug, prosecutors said. 

Body camera footage appeared to show Familia trying to conceal and destroy a white power alleged to be fentanyl, according to state attorneys.

Prosecutors also said that a search warrant executed at her home also turned up fentanyl. 

Familia pleaded not guilty at the arraignment, the local TV station reported.

Her attorney asked for a bail of $10,000, citing the undue financial burden it would place on Familia’s family, though the judge still held her on a $250,000 bail.

She is due back in court on Nov. 20. 

An attorney for Familia did not immediately respond to The Post’s request for comment.