There is a quote in the new June episode of JW Broadcasting, which says Isaiah 11:6 applies to people inside the Congregations now who have their personalities transformed.
In the 1980's and 1990's, when I attended meetings all the time, I always heard them say this Scripture had a LITERAL fulfillment and the animals will be at peace with one another.
Here is the Scripture:
Isaiah 11:6 (NWT): The wolf will reside for a while with the lamb, And with the young goat the leopard will lie down, And the calf and the lion and the fattened animal will all be together; And a little boy will lead them.
After hearing the quote, I did a search on JW.org, and I found this statement regarding that Scripture:
Isaiah Book 1, Pages 163-165:
Do these words not touch the heart? Notice that the peace described here results from the knowledge of Jehovah. Hence, more is involved than mere safety from wild animals. The knowledge of Jehovah will not change animals, but it will affect people. Neither on the way home nor in their restored land will the Israelites need to fear wild beasts or beastlike men.—Ezra 8:21, 22; Isaiah 35:8-10; 65:25.
14 This prophecy, however, has a larger fulfillment. In 1914, Jesus, the Messiah, was enthroned on heavenly Mount Zion. In 1919 the remaining ones of “the Israel of God” experienced release from Babylonish captivity and shared in the restoration of true worship. (Galatians 6:16) As a result, the way was opened for a modern-day fulfillment of Isaiah’s Paradise prophecy. “Accurate knowledge,” the knowledge of Jehovah, has changed personalities. (Colossians 3:9, 10) Formerly violent people have become peaceable. (Romans 12:2; Ephesians 4:17-24) These developments have now affected millions because Isaiah’s prophecy has come to include a rapidly increasing number of Christians with an earthly hope. (Psalm 37:29; Isaiah 60:22) These have learned to look to the time when the whole earth will be restored as a secure, peaceful paradise, according to God’s original purpose.—Matthew 6:9, 10; 2 Peter 3:13.
15 In that restored Paradise, will Isaiah’s prophecy have a further, perhaps more literal, fulfillment? It seems reasonable to think so. The prophecy gives to all who will live under the Messiah’s rule the same assurance that it gave to the returning Israelites; they and their children will not feel threatened by harm from any source—human or animal. Under the Messiah’s Kingdom rule, all earth’s inhabitants will enjoy peaceful conditions like those that Adam and Eve enjoyed in Eden. Of course, the Scriptures do not reveal every detail of what life was like in Eden—or of what it will be like in Paradise. We can be confident, though, that under the wise and loving rule of the King Jesus Christ, everything will be just as it should be.