When she sees her niece, she falls in love.
It takes an instant.
And nothing matters. It doesn't matter why that baby has been created, that she'll never be able to have this, it doesn't matter she has hated her existence, that the darkness has screamed at her to end her little life – countless times. It doesn't matter, because wanting this beautiful little bundle of pink and white and softness away, wanting her hurt, is something her brain can't even process right now.
Nothing matters but this instant.
She'll deal with the rest later. For now, she's just an aunt.