Her memories of what her body looked like before she had a child lingered in her mind.
They have a poor self image.
In her before picture Siobhan is actually wearing her beginning outfit for her session sans makeup, no retouching, straight out of camera.
With no boyfriend, Molly knows of only one other person she can trust to do this.
She wanted all her images shared, and the reason behind why she was doing this for herself spotlighted.
Molly is hesitant, but listens to her sons instructions, photos being snapped of his mom sucking him off.