Need formula or VBA code to count

[winmaxservices]

I have data in a table
Column A is serial number, B is relation.
In C I want to give family code to each family starting from 1. For example code for first set of family should be 1 and second should be 2 and so on.

In D I want to give family members count in each family For example count first set of family. please refer attachment. I have given some examples.