(Something I just thought of for the mystery bait shop similar to the scene with when ford became canon)
Mabel: do it dipper stop the spell!
Tate: dipper no! Don't stop the spell you gotta trust me!
Dipper: I don't even know you are anymore Tate
Tate: listen dipper everything I've been workin for all comes down this spell
Mabel: don't trust him dipper! He lie to us!
Tate:everything I've ever done its been for this family. For pops and ya kids so tell me do ya think I'm a bad person? Look me in the eyes and tell me I am if ya do
Mabel: just stop the spell dipper!
Dipper: Tate. ...I trust you
Mabel: dipper no!
*Light explosion*
???: *stands in the center of the spell grounds*
Mabel: who's that tate?
Tate: spring mcgucket pines....the writer of the notebook
Spring: *removes scarf revealing face*
Tate: my sister