Hello everyone,

I have a panel dataset of individuals (children). There, I have the individual's and their mother's ID and mother's income. I also have their birth years, the survey year, and much more.
What I would like to do is create a variable that equals 1 (or the income) for each child only in the first (lowest) year observed within the datapanel.
I need the mother's income at the time the household was surveyed the first time and tried something like:

sort child_id year
gen mother_pay = mother_pay_dv if min(year)==1

Then I tried something like:
bysort child_id mother_pay: egen mother_pay = mother_pay_dv if min(year)==1

I thought Stata would give me the pay of the mother for the first (minimum) year the household was observed but this doesn't do what I need. I'm also not using the syntax correctly but don't understand the help so well when it gets a bit more technical :-/


Any suggestions, please?


Here is a data example:
birthy age year child_id mother_id mother_pay_dv
1997 0 1997 1400962 5285651 18013.86
1997 1 1998 1400962 5285651 28221.71
1997 2 1999 1400962 5285651
1997 3 2000 1400962 5285651 32424.94
1997 4 2001 1400962 5285651 65000
1997 5 2002 1400962 5285651 91000
1997 6 2003 1400962 5285651
Thank you!