Count returns false value if childgroup contains elements

Hi,

I got the following Data-Structure:

Group1: 2 rows with the same value in all columns

Childgroup1: 3 Rows with different values. 

My Row group structure looks like this: 

Group 1:         ValueA_1

Childgroup1:         ValueB_1

                            ValueB_2

                            ValueB_3

Making a count on ValueA_1 will produce 3 in this case. I would like it to produce 2.