I should have said you can't remove a physical action once it has been taken by one of the two protaganists themselves. She doesn't need something casual to spark her or her father's actions in a loop. Her personal timeline's actions remain in play and in her memory even as the world shifts around her. She doesn't need a reason to have told her father those things, because it is actions she has already taken. of course the shed and what not changed as the timeline shifted around her. Her and her father are the lynchpins that cause the changes and hold the timeline together. They do not answer to anything paradoxical as they themselves are the paradox.