Can I reciprocate with gifts at christmas?

Since converting to Islam I've always attended my (atheist) family's Christmas celebrations (though they are *not* celebrated in a religious way). My parents expect me to give gifts to my family, and I know how important this gift giving is to them, and how highly regarded parents are to a Muslim. I found a hadith (emailed to me by a friend) that seems to support my logic: >Narrated ‘Aisha: > >Allah’s Apostles used to accept gifts and used to give something in return. > >(Bukhari, Volume 3, Book 47, Number 758). Is it Halal to reciprocate with gifts in this fashion, though it is haram to celebrate a religious holiday not form Islam?