Infants learn different things in different ages. Let's say infant A learns to speak at age 1 (I have no idea what is normal), and infant B learn to speak at age 1.5. Does the age of learning say anything of who will be better (at any skill) in grown up age?
We know that it is easier to master something that we are truly interested in, as the interest will motivate and fuel us to progress. We also know that personal characteristics and general interests start at very low age and possibly before birth. Based on this, it would make sense if infants with an inborn interest for something (for instance language) are faster at learning the relevant skill (talking) than infants with less interest in it. Is there any research on this?