Cultural Ceremony Or Religious

I have a family member having a cultural ceremony for their baptized child. When I looked up the ceremony, I saw that this was originally a pagan ceremony tied to giving gifts to different gods for the protection of the child. Food is distributed to each of the gods, followed by prayers for health, wealth, and luck. I know that my family member is a nonpracticing Christian and likely doing this to tie the child to cultural traditions - but would it be a sin (possibly against the first commandment?) for us Catholics to attend. Can we attend and not participate in the ritual aspect, if it is performed?

I know, for example, that Halloween parties started out as pagan rituals and now have evolved into costumes and candy... so perhaps I'm being overly cautious, as well.

Thanks!

Sorry if this is in the wrong spot...still new :)

Credit: goddesses-and-gods.blogspot.com