Hello,

I wonder if anyone could help with the following:

I have 2 variables with unique identification (ID) numbers with over 30 years of follow-up time. One is ID numbers for children and the second is the ID numbers of their mothers.
Example:
ChildID:-------------MotherID:
10---------------------------20
11---------------------------21
12---------------------------10
13---------------------------22
I want to identify children who are now also mothers in the dataset. For example Child ID10 above is now also a mother. Is there a way I can create a variable to identify which children subsequently became mothers based on their ID numbers?

Thank you,

Gillian