Baby Shrek is the name given to Shrek's childhood counterpart in Shrek the Musical. When he was seven, he was kicked out of his parents' home. This was part of a "tradition" for ogres to send their young off at an early age. Eventually the time arrived, and Shrek was sent off to the big world.
Instantly, he was ridiculed by everyone he came across, from scared villagers to rude children. Only one strange girl walked passed him showing any sign of kindness. She waved at him, putting on a genuine smile.