Weight increase in week 4 is a "measly" 325g.  Actually, looking at our Plunket weight charts, he is only just above the 50th percentile for weight (ie, slightly above average).

However, length & head circumference tell a different story.  Both of these are above the 97th percentile!

To give some idea of what this might mean, his current length translates into a height over 6'3" as an adult!
If this is the case the then he will tower over both his parents...
(and he will have a big head like his father and grandfathers)