The mother of Star Hobson could face more time in prison for her role in the toddler's death after a ruling by the government's top legal adviser.
But the sentence given to the woman found guilty of murdering the 16-month-old, from Keighley in West Yorkshire, will not be increased.
In December, Star's mother Frankie Smith, 20, was handed an eight-year sentence for causing or allowing her daughter's death.
Her partner – bouncer and security guard Savannah Brockhill, 28 – was found guilty of murder and jailed for life with a minimum term of 25 years.
The Attorney General, Suella Braverman QC, today ordered a review of the prison term given to Smith after complaints that it was unduly lenient.
But she said the sentence given to Brockhill could not be reviewed.
In a statement, Ms Braverman said: "This case will have caused upset to anyone who read about it, but my job is to decide if a sentence appears to be too low based solely on the facts of the case.
"I have carefully considered the details of this case, and I concluded that I can refer Frankie Smith’s sentence to the Court of Appeal as I believe it is unduly lenient.
"However, I have concluded that I cannot refer Savannah Brockhill’s sentence.
"I can only challenge a sentence if it is not just lenient but unduly so, such that the sentencing judge made a gross error or imposed a sentence outside the range of sentences reasonably available in the circumstances of the offence.
"The threshold is a high one, and the test was not met in this case."
Star, who was 16 months old, suffered the "catastrophic" injuries which killed her at her home in September of 2020.
But she had been repeatedly attacked and abused by the pair during her short life.
The Conservative MP for Keighley and Ilkley, Robbie Moore, told ITV News that he was pleased that the sentence was going to be reviewed.
"Eight years in my view was absolutely not strong enough for the vile treatment that that child went under and the mother allowed effectively all of those events to happen which ultimately led to the murder," he said.
"Of course, I'm disappointed that the case of the partner is not being referred to the court of appeals.
"My view is that if you are convicted of murder, for a toddler, there is a strong case to argue that we should be much tougher than 25 years."
What is an unduly lenient sentence and who decides?
Anyone can ask for someone's crown court sentence to be reviewed if they think it is too low.
The request must be made within 28 days of the original ruling.
Only certain types of crime can be reviewed, including:
Certain other crimes falling under the following categories: child sex crimes and child cruelty, serious fraud, drug crimes, terror-related offences, hate offences, stalking and harassment
Requests are made to the Attorney General's Office, which then decides if the case should be referred to the Court of Appeal. The appeal court decides the revised length of the sentence.
It will now be up to the Court of Appeal to decide what sentence Smith should receive.
A date for that hearing has not yet been set.
Ms Braverman added: "This is a tragic and extremely upsetting case and my thoughts are with all those who loved Star Hobson.
"This vulnerable and innocent child was subjected to continued physical abuse, and her mother, Frankie Smith, allowed it to happen."