Yes, if the situation of the researcher changes, the Family Allowance can become ineligible. If the relationship is no longer bound through marriage/ other legal agreement, then they are no longer eligible to receive the allowance.
The researcher is obligated to inform of this change of situation if it occurs.
Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the Research Executive Agency (REA). Neither the European Union nor the REA can be held responsible for them.