The Sheep of the Fold
                T'was a sheep, not a lamb, that wandered away
                In the parable Jesus told—
                A grown-up sheep that had gone astray
                From the ninety and nine in the fold.

                Out in the wilderness, out in the cold
                T'was a sheep the good shepherd sought;
                And back to the flock, safe in the fold,
                T'was a sheep the good shepherd brought.

                And why for the sheep should we earnestly long
                And as earnestly hope and pray?
                Because there is danger, if they go wrong,
                They will lead the young lambs away.

                For the lambs will follow the sheep, you know,
                Wherever the sheep may stray.
                If the sheep go wrong, it will not be long
                Till the lambs are as wrong as they.

                And so with the sheep, we earnestly plead
                For the sake of the lambs today.
                If the lambs are lost, what a terrible cost
                Some sheep will have to pay!

                (C. D. Meigs)

(Quoted by Patricia Pinegar, BYU Family Expo, April 6, 1999)  (link to her address)

This poem was also quoted at the BYU Women's Conference, April 2000, but was attributed to C.C. Miller and entitled "The Echo".

Also, this poem (it varies a little) was used by Elder Ben Banks in Oct. 1999 Gen. Conference   (link to talk) with the reference below:

                    The Echo

          Twas a sheep not a lamb that strayed away
          In the parable Jesus told,
          A grown-up sheep that strayed away
          From the ninety and nine in the fold.

          And why for the sheep should we seek
          And earnestly hope and pray?
          Because there is danger when sheep go wrong;
          They lead the lambs astray.

          Lambs will follow the sheep, you know,
          Wherever the sheep may stray.
          When sheep go wrong, it won't take long
          Til the lambs are as wrong as they.

          And so with the sheep we earnestly plead
          For the sake of the lambs today,
          For when sheep are lost, what a terrible cost
          The lambs will have to pay!
 

     ("The Echo," C. C. Miller, quoted in Hugh B. Brown, The Abundant Life [1965], 166­67)
 
 

So, I don't know which is the correct title and author.