Should I fill in the family information clearly when interviewing for a job?

It can be seen from your question that you are a very delicate and thoughtful person.

You are right. A lot of personal information is leaked through these channels and occasions.

Your concern is also justified. You can try to explain it to the recruiting unit first and see if you can accept your opinion.

Employers may also want to fully understand the applicant's situation, such as family background and whether social relations can be used. However, these ideas have virtually violated the privacy of candidates, so we should summon up courage to safeguard our rights and interests.

If I were HR, I would fully understand the concerns of the candidates.

In fact, when you are applying for a job, you can also distinguish different levels of recruitment units. This is a two-way choice. For an organization that doesn't respect employees' privacy, candidates should think carefully.

When I applied for a job before, I met such a unit, usually from the side. If not, I will give up.

Be bold and cautious. I wish you success!