This case is difficult for statement analysis because the full story given to LE hasn't been released to the public. I've even seen a time of 6pm for Mariah going to bed.
KH saying she fed Mariah strikes me as odd. Fed her what, a bottle? A 3 year old might still take a bottle but doesn't usually require feeding, especially the independent ones, unless not well.
BBM
It may be a figure of speech. I say that all the time, be it adult, or child. I fed xxxxx before they went home (or went to bed).