There are very many factors that determine the intelligence of a human being regardless of age. Certainly all parents long for their children to develop their innate abilities to the fullest, however, there is a general belief that intelligence is largely determined by a person's genes, that it's simply inherited. We believe that while a child is always born with certain traits that set him or her apart from even their parents and siblings, let alone the rest of mankind, their brain and intelligence by and large are like their bodily frame, e.g. their muscles, highly malleable (called the "plasticity of the brain" in modern neuroscience).