Space Ballet: 2 Neptune Moons Perform an Unusual Pas de Deux

After reading the report and cited reference, it seems that the long term stability of this orbital configuration - may not show it can remain stable over some 4.5 billion years or more, NASA Finds Neptune Moons... There are various reports too on the age of Saturn ring system too indicated issues with long age and long time stability. Triton retrograde orbit is always interesting topic.