Honestly, I can't stand to look at her so no idea where or when she wears a cross.
But I think she needs to bear in mind the words of Jesus:
Matthew 6: 1-4
"1-Beware of practicing your righteousness before other people in order to be seen by them, for then you will have no reward from your Father who is in heaven.
2 Thus, when you give to the needy, sound no trumpet before you, as the hypocrites do in the synagogues and in the streets, that they may be praised by others. Truly, I say to you, they have received their reward.
3 But when you give to the needy, do not let your left hand know what your right hand is doing,
4 So that your giving may be in secret. And your Father who sees in secret will reward you.