Following are a number of back-translations as well as a sample translation for translators of Proverbs 18:19:

• Kupsabiny: “It is hard to reconcile a friend who is annoyed/offended,
  than to destroy a protected city.” (Source: Kupsabiny Back Translation)
• Hiligaynon: “You (sing.) find-it-hard to reconcile to your (sing.) sibling who had-bad-feelings against you (sing.). This seems harder to do than to attack a stoned-wall city.
  As hard as to destroy the bars/locked of the gate of a palace, it is also hard to stop the fighting of two people.” (Source: Hiligaynon Back Translation)
• Kankanaey: “It is more-difficult to return (i.e., get-back) the companionship of a friend whose feelings (lit. thoughts) have been caused-pain than the way to get-through the fence of a city.” (Source: Kankanaey Back Translation)
• English: “If you help relatives, they will protect you like a strong wall protects a city,
  but if you quarrel with them, that will separate you from them like bars on a city gate separate the city from those who want to enter it.” (Source: Translation for Translators)