Complex sentence: The Smith family says the overnight stay at Gavin's friend's home was planned, despite recent marital difficulties that had led Evan Smith to criticize his father for "leaving the family" in a tweet (since deleted) two weeks earlier.
Split into simpler sentences: The Smith family says the overnight stay at Gavin's friend's home was planned. Recent marital difficulties had led Evan Smith to criticize his father for "leaving the family" in a tweet (since deleted) two weeks earlier.