rolling up data at various levels based on a numbering system

[Sherry]

My data looks like this:
col A Col B Col C
1.0 General
1.1 Test 1.1 10
1.2 Test 1.2 10
2.0 Scope
2.1 Test 2.1 10
2.2 Test 2.2 10

I need to do two things;
(1) Verify that data exists for 1.1, 1.2, 2.1,& 2.2 (the lowest level)
(2) Sum 1.1 & 1.2 with value in 1.0 and Sum 2.1 & 2.2 with value placed in
2.0.

This is a simplified version of what I really need to do because I may have
a 1.2.1, 1.2.2, etc. Basically I want to verify that the user has entered
values in Col C for the lowest levels only and then sum those to the next
level.

I know this will have to be done with a macro.

Thanks for any guidance you can provide!
Sherry