Good morning
I need some advice for my master thesis please.

My data is a cross-sectional survey. About 11000 households. I'm studying the effect of some disease on the investment in human capital of the siblings of the children who are sick.
I have the disease status of children under 5 years old in each household. I've created a dummy variable which takes the values 0, 1 or 2 if there is 0,1 or 2 sick children in the household. My equation looks like this:
EDUij = ⍺i + 𝜸j + 𝜷1 STATUSj + 𝜷2 EDU_MOTHERij + 𝜷3 WEALTH_INDEXj +... + 𝛆ij
i for a child, j for a household.
I am wondering how to specify to Stata that my right-hand-side variable is valid only for children who are NOT sick, so that i can see if they have been impacted in terms of education due to the sickness of their siblings.

I hope it's clear enough.

Thank you for your help