What can a girl do if her in-laws don't allow her to wear the hijab?

Veil is an important thing for Muslims girls in Islam. My friend is suffering a problem which is related to the veil(Hijab). She used to wear Hijab from her school life but after marriage her in laws (including her husband) do not allow to wear the veil. **What should she do? Does she argue and protest with her in laws or stay patient and follow their wishes?**