Possible Clues:

• It's not part of SOS
• "— Gang"
• "O Canada! ___ home and native land!"
• My and his
• "The Fault in __ Stars": 2014 film
• With 26-Across, it 'will come,' in song
• Sinclair Lewis novel '___ Mr. Wrenn'
• "— Lips Are Sealed"
• Pronoun for us
• Mine, partially