Mother Yasoda was thinking of Krsna as her child. Although He is beyond the reach of all senses, she endeavored to bind Him up to a wooden grinding mortar. But when she tried to bind Him, she found that the rope she was using was too short--by two inches. Mother Yasoda was smiling, but she was astonished. How was it happening?
Krishna Book Chapter 9: Mother Yasoda Binding Lord Krsna
"Before His personal appearance, the Lord causes some of His devotees to appear as His mother, father and intimate associates. He then appears later as if He were taking birth and growing from a baby to a child and gradually into a youth."- CC Madhya 20.379