I have household-level panel data from two time periods.

I found out that a good portion of my households have missing values in some variables that I need to control for, in the second time period.

In this case, given the fact that the fixed effects model focuses on the within variation, will it be flawed/pointless to only keep the first year values of those households (shaped 'long' in Stata) that have missing values in the second time period? Or, should I exclude those households altogether?

Thanks!