Complex sentence: Stewie meets his past self and tells him about his bad alternate life and together they stop the fighting by reminding Peter & Lois of how much they love each other by leaving Peter's "I Love You" picture to Lois in the refrigerator.
Split into simpler sentences: Stewie meets his past self and tells him about his bad alternate life. Together they remind Peter and Lois of how much they love each other by leaving Peter's "I Love You" picture to Lois in the refrigerator.