On the consciousness of a new born baby

[Belacqua]

What is the difference between a fetus of 8 months and a new born baby in terms of consciousness?

Mainly the newborn has more to be conscious of. It has a great deal of sensory input, whereas when it was in the womb it had much less. 

Is any of them aware of their existence? Does anyone have memories one hour, day, week after being born? 

I don't think that it has awareness of itself either inside the womb or for some time after it comes out. Self-awareness requires some development, some experience that the world consists of both me and things that are not me. 

A great deal has been written by developmental psychologists about how the newborn develops its sense of being separate from its mother, and how it learns to distinguish figure from ground. It has sensory input, but until it can distinguish among separate things, it has no sense of self. 

Can we say a new born is truly alive (understand conscious of its own existence)?

Are you saying that something without consciousness of its own existence isn't truly alive? That seems problematic to me. 

Plants are alive. Animals at all levels of awareness are alive. Unconscious people are alive. Being alive and being a person are separate questions. 

This question is related to even a bigger question of what is consciousness, but it has some immediate implications. For example, if a new born baby dies 1 day after being born, can we say a person died? Physically speaking yes, but what about personality, memory, feelings, consciousness? Does it make sense for parents to mourn the death of the baby, if it was never truly a person to begin with? A new born baby crying is not really conscious that its crying, rather it is a natural reflex.

What are your thoughts?

After conception the thingy develops its potential. There is no strict boundary line between calling it not-yet-a-person and a person. For practical reasons the law may make a distinction, but there is no ontological change. 

In the womb it develops its potential. After it's born it continues to develop its potential, and goes on doing this until it dies -- at what we hope is a ripe old age. 

If you want to declare some marker to declare that the thing has gone from non-person to person, there are various things you could point to. But these are more legal questions than biological ones. I don't see how we can say that a newborn who hasn't yet developed a noticeable personality is less of a human being than a child who has begun showing unique traits. 

These days we all believe that a person's sexuality is something we are born with. Straight people are born straight long before they are aware of what sexuality is, or have a word for it, or can articulate their desire, or are conscious of being straight. This means that the personality is there, innate, from before birth. It just hasn't shown itself yet. To me, this indicates that the manifestations of the characteristics you suggest (personality, feelings, etc.) do not determine whether something is human or not.