Frankie Smith, aged 20, and Savannah Brockhill, aged 28, both deny killing Star Hobson. Star Alyssa Hobson from Keighley, West Yorkshire, suffered a cardiac arrest and died in hospital on September 22 last year.
The young girl was kicked, stamped and slammed, Bradford Crown Court heard.
The pair allegedly performed wrestling moves on the infant, as well as calling her a “little c***.
According to the Telegraph and Argus, Ms Smith’s half-sister Alicia Szepler told the court that the couple would “choke slam” the child, adding that Star was called “names that shouldn’t be said to a child”.
She said: “Star would do a do a fake laugh and Smith would say, ‘Shut up you little c*** laughing like that’.”
When Star’s grandmother confronted Ms Smith about the “choke slam”, the 20-year-old said the technique had been used to “toughen up Star”, the court heard.
The court was told that Star’s injuries were blamed on another child.
Ms Smith and Ms Brockhill also allegedly made the toddler face wall if she misbehaved.
Ms Smith’s mother told the court of one occasion where she “felt sick” when Star was forced to face a wall in a Wetherspoons when she refused to eat her meal.
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“My family always said stop mixing with a lower class I should have listened.
“Get gone you little vermin, you bad omen. Your family was right about you, you need Lynfield Mount.”
She also allegedly called Star a “very nasty and naughty child” and “a brat who thinks nothing of you”.
When medics arrived at the property, jurors were told that they discovered the body of an apparently “lifeless baby wearing only a disposable nappy”.
Alistair McDonald, prosecuting, told the court that Star suffered such catastrophic injuries that “there was never any real chance of saving her life”.
Mr McDonald also said that the young girl had suffered fractures to her shin, ribs and skull as well as lacerations to a vein carrying blood between her leg and organs which leaked into her abdominal cavity.
The pair deny charges of murder and causing or allowing the death of a child.
The trial continues.