Jan Urey, of the Crown Prosecution Service, said:
This was a wicked attack against a vulnerable and defenceless child, perpetrated by Daniel Rigby.
The injuries suffered by Rio were brutal and could not have been inflicted accidentally, as Rigby had claimed in an attempt to hide what he had done.
Today, a jury has decided that Rigby caused Rio's death and that Kirsty Smedley betrayed her responsibility to keep her child safe from Rigby's violence.
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