They would just lie about the candidate being "insuitable" in some other way. Why on Earth would an applicant's parental info be relevant, in any case?
Which is why I wonder why candidates bother putting useless information on their CVs, such as:
- father's name
- product descriptions for projects they've worked on
- what primary school they went to
- passport number
Instead of useful information like:
- year of graduation and degree classification
- how much they paid for their qualification (for Indians only)
- subjects for qualifications
- actual contributions to projects