The scriptures attest to the reality of the person, the baby, that exists in the womb. When Mary visited Elizabeth her cousin who was great with child, John the Baptist, she called to Elizabeth and the baby in her womb leaped for joy! Elizabeth was filled with the Holy Ghost and she knew exactly what had just happened, for it was revealed to her.
Luke 1:44 For, lo, as soon as the voice of thy salutation sounded in mine ears, the babe leaped in my womb for joy.
39 And Mary arose in those days, and went into the hill country with haste, into a city of Juda;
40 And entered into the house of Zacharias, and salutedElisabeth.
41 And it came to pass, that, when Elisabeth heard the salutation of Mary, the babe leaped in her womb; and Elisabeth was filled with the Holy Ghost:
42 And she spake out with a loud voice, and said, Blessedart thou among women, and blessed is the fruit of thy womb.
43 And whence is this to me, that the mother of my Lord should come to me?
44 For, lo, as soon as the voice of thy salutation sounded in mine ears, the babe leaped in my womb for joy.
Source for HD video: https://www.lds.org/bible-videos/videos/mary-the-mother-of-jesus?lang=eng
Bible Video of Elizabeth's babe, John, who leaped for joy upon hearing Mary's voice, who carried Jesus the Christ. These babes knew of each other.
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