Question

How much memory can a two-year-old child’s brain hold?

Answer 1

A two year old can memorize faces, colors, social emotion, words and movement. They can actually memorize a lot for their small age. Of course they can't remember big details and such but they still can recognize small details. 

Answer 2

That is very individualized as a lot depends upon how much exposure that child has had to one on one learning. Of course a child who has been read to daily, had much encouragement to talk , explore and be nurtured is probably going to do much better than one who has not. At two, every single month makes a difference so you are going to see a lot of variation between a 24 month old and a 30 month old. Some two year old children will have a large vocabulary and know their ABC's by sight at 2 1/2. Other couldn't tell you at 5. If you are speaking of recalling a person or a name, a child at 2 is going to need many exposures to remember that name . Traumatic events will affect how a child meets later challenges, but they usually can't remember specifics that aren't reinforced by repetition.