.
Keegan suffered seven broken ribs, broken legs and severe head and spine injuries before she died.
The toddler had 153 scars on her body, including her face and neck, when she was killed.
She was also suffering from an untreated broken leg, which would have made even the slightest movement agony.
It is not known whether the Appeal Court will hear Downer's plea.
The mum-of-four, who killed Keegan eight months after fostering her, protested her innocence throughout her three-week trial at Birmingham Crown Court.
Sickeningly the "vicious and unfeeling" mum even tried to blame the murder on her teenage son, who she claimed took charge of Keegan's "day-to-day" care.
Keegan, also known as Shi-Anne, was put in Downer's care after Birmingham City Council approached the business student about the child.
She spent the first 10 months of her life under the care of experienced foster mum Jane Murray, who later raised concerns about the little girls' treatment under Downer.
Jane flagged up concerns Downer was motivated by cash and said Keegan had not been seen by a health visitor for months before her death.
After an extended period of horrific abuse, Keegan finally suffered septicaemia, infection, blunt chest trauma and head injury.
In a bid to save her skin, Downer delayed calling 999 after landing a deathly blow on the child and instead drove off to dump Keegan's blood-stained mattress.
Little Keegan was eventually taken to Birmingham's Children Hospital, but it was too late to save her.
Foster mum Jane said at the time of Downer's conviction: "Not a day goes by when I don't think of Shi-Anne. I have videos and pictures.
"She was never the kind of child who clung on to you, she was never difficult. There was nothing that was a concern. At Christmas, I had to physically take her to the tree.
"The hardest part of the case was seeing a picture of Shi-Anne at a barbecue. It was supposed to show she was alright. I looked into her face and could see she was far from alright."
Jane declines to comment on social services role in Keegan's care.
She said at the time: "My family and friends were a huge part of Shi-Anne's life and we all miss her terribly, but no amount of tears or regrets will bring her back.
"Kandyce Downer was her guardian, there is a difference. The biggest difference is that my assessment for fostering took two years and hers took a mere few months. You can take what you want from that."
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