The previous Lubavitcher Rebbe, once recounted a story that occurred with his father, Rabbi Sholom Dovber of Lubavitch:
“When my father was four or five years old he went to his grandfather, the Tzemach Tzedek, on Shabbat Vayeira, and began to cry as he asked, “Why did G-d show Himself to our father Avraham – but He does not show Himself to us?” The Tzemach Tzedek answered him: ‘When a tzadik decides at the age of ninety-nine years that he should be circumcised, he deserves that G-d appear to him.'”
Although this story occurred with a child who would grow up to be a rebbe, there is nevertheless an important message that we are to learn.
Often times, when educating our children we abstain from discussing things that we deem to beyond their understanding. We assume that a child cannot appreciate G-dly matters so we instead focus on inspiring them for some material gain.
This story expresses that even a young child of four or five years of age can desire G-dliness to the extent that he can be brought to tears.
When educating our children we should imbue within them a desire to appreciate G-dliness and spiritual pursuits. It is only through such an education that a child can grow up to be a rebbe.
 Hayom Yom, 9 Cheshvan.