Complex sentence: Lucy selects the largest one they could find, and poor Linus has to be the one getting it back to the house, only to be very distraught when it turns out Lucy is going to gut it to become a jack-o-lantern.
Split into simpler sentences: Lucy selects the largest they can find, and poor Linus has to get it back to the house. He becomes distraught when it turns out Lucy is going to gut it to be a jack-o-lantern.