bills Perfect butterfly

So after weirdmageddon Ford,Mabel,dipper,stan,soos,wendy gideon,robbie,Pacifica,and old man mcgucket all thought they killed bill but they were wrong what they didn't know was in two years he would come back and takes dipper,Mabel,and Pacifica to another dimension called monster fall but little Mabel,dipper, AND Pacifica know that he took them to the dimension they were born in and so Mabel and dipper have been caterpillars for fifteen years and Pacifica a siren for the same amount of time and didn't know it they very vague memories when they were two but once they told their moms about the dream they were having both mom's told Ford and so he came with the memories gun and erased the memories of them ever being there.