Complex sentence: Abigail raised her two younger sons throughout John's prolonged absences; she also raised her elder grandchildren, including George Washington Adams and a younger John Adams, while John Quincy Adams was minister to Russia.
Split into simpler sentences: Abigail raised her two younger sons throughout John's prolonged absences. She also raised her elder grandchildren, including George Washington Adams and a younger John Adams, while John Quincy Adams was minister to Russia.