“Mother-croon of bird” is the gentle humming voice of a mother-bird to its baby. The song is not sung in a hushed voice, but it is heard in the hushed moments of twilight, as then the noises in the surroundings gets reduced.
Answer: “Mother-croon of bird” is the mild buzzing voice of a mother-bird to its baby. The tune is now not sung in a hushed voice, however it is heard in the hushed moments of twilight, as then the noises in the environment receives reduced.
