Children are baptized as members of The Church of Jesus Christ of Latter-day Saints when they reach age eight and receive a bishop's interview to assess their understanding and commitment. This age for baptism was identified by revelation (D&C 68:25, 28). The Church does not baptize infants.
The practice of baptizing infants emerged among Christians in the third century A.D. and was controversial for some time. According to the Book of Mormon, it similarly became an issue and was denounced among the Nephites in the fourth century A.D. When Mormon, a Nephite prophet, inquired of the Lord concerning baptism of little children, he was told that they are incapable of committing sin and that the curse of Adam is removed from them through the atonement of Christ. Hence little children need neither repentance nor baptism (Moro. 8:8—22). They are to be taught "to pray and walk uprightly" so that by the age of accountability their baptism will be meaningful and effective for their lives.
McConkie, Bruce R. "The Salvation of Little Children." Ensign 7 (Apr. 1977): 3—7.
Robert E. Parsons