Complex sentence: Later, while Lottie, Mickey and Jess are playing, Gordie dies, and due to having no phone signal Lottie runs back to the house to tell the adults, leaving Mickey and Jess with Gordie's body.
Split into simpler sentences: Later, while Lottie, Mickey and Jess are playing, Gordie dies. Left without a working phone, Lottie runs back to the house to tell the adults, leaving Mickey and Jess with Gordie's body.