During the period when settlers spent a lot of time cutting wood, if a son looked or acted like his father he was called a “chip off the old block”.
It meant that except for size, the two were as clearly related as a chip cut from its original block of wood from the family tree.
A little shaver is the same, except that a shaving is smaller than a chip.
A “sprig” on the other hand, is a child too small yet to even have a branch on the family tree.