Irrelevant questions on job application form

[Qcarchoo]

A friend's wife has recently applied for a part-time job at their local garden centre.
On the application form it asks for her maiden name and the names and ages of her children.
Can anyone enlighten me as to why a garden centre would need this information?

[Vaud]

It's irrelevant and probably unlawful, though IANAL.

Probably an ill advised manager wanting to either include or exclude a certain demographic.