I think my au pair might be lying about her age

[Anonymous]

Our south african aupair was from an area near Zimbabwe. She told us that she didn't really know her birthday because in her culture, their parents randomly pick a day to celebrate their birth. It wouldn't be a stretch that someone could get a birth certificate to falsify the year. They falsify driver's licenses and health certificates there often.

The question is, "why do you care?"
Is she a good aupair? Are your children taken care of? Would it change anything?

They need to be under 27 to travel here on the aupair visa. Are 2-3 years really worth the drama?