Although, the two words looks the same, in that, they are used to refer to babies, there are still some differences between them. Not many people will know an infant is quite different from a toddler. In fact, these words are used interchangeably when referring to babies. According to my research, I discovered the word 'infant' is used to refer to babies that are not up to a year. Toddler, on the other hand, is used to refer to babies that are between a year and three years.
While this might not be true in some instances, because there are some cases we refer to an already grown up boy as a toddler, actually not because he is really a toddler, but because he has not fully matured. This means we can use toddler for younger people. While infant, is not usually used in the same context as toddler, because it is generally used to refer to a very young human being, from birth to somewhere between six months and a year of age.