Complex sentence: His long absences and change in personality drive a wedge between Pistone and his wife and three children, knowing that the slightest mistake in his performance as a mobster could result in death to him and his family.
Split into simpler sentences: His long absences and change in personality drive a wedge between Pistone and his wife and three children. Meanwhile, the slightest mistake in his performance as a mobster could result in death to him and his family.