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.
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.
Suicide is not something to joke about. Which is why if your friend is going through some tough times considering it. You should persuade them not to do it.
Dog owners tend to live longer and far better after a heart attack or stroke. Researchers found that there were 33% lesser chance of death to occur in a person who is the owner of a dog after a heart attack. Dogs tend to calm the humans.