Complex sentence: The Tucks explain to Winnie that the spring is a magical one that grants eternal life to anyone who drinks its water and that they discovered its effects by accident after heading to the Treegap area to try and build a new life for themselves.
Split into simpler sentences: The Tucks explain to Winnie that the spring is magical and grants eternal life to anyone who drinks its water. They discovered its effects by accident after heading to the Treegap area to try and build a new life for themselves.