Possible Clues:

• "___ we forget" (Kipling phrase)
• Let's make this, just in case
• Word stated before we forget
• Fearing that
• Kipling's "___ we forget!"
• "___ we forget ..." (Kipling)
• In order not to, to avoid the risk that
• In order not to - . . . . we forget
• ''___ we forget ...'' (Kipling)
• ''Judge not, ___ ye be judged''