Dear Sister,
It depend on the purpose of your attendance. If your attendance have such a positive impact to your family about Islam, then you can go.
Shaykh Muhammad bin Salih Al Uthaymeen, may Allaah have mercy say, "If the invite is from a non muslim, may not (haram) to meet the invitation, even sinful, unless there are serious benefits (maslahat) in it. Like to ask him/her to convert to Islam or in the framework of peace. Things like this is okay because the Prophet sallallaahu 'alaihi wa sallam had attend the invitation from the Jews in Medina. "(Sharh Riyadhus Sholihin).