The baby is unresponsive and you want to teach it to respond?
Yes. But i think "to teach him or her"
If one knows the sex of the baby, then it is correct to use the gender-specific pronoun. But, if one does not, then the gender-neutral "it" is acceptable. Torturing babies and grammar is also acceptable in certain circles.
Since when is there a difference between baby and infant that they cannot be used interchangeably?