Help a Gentile Out – Bar Mitzvah Gift (United States)

I (non-Jewish) have been invited to a Bar Mitzvah reception for the son of a woman that works for the team that I manage at a large company. In addition to working for me, we are what I would categorize as good “work friends” but we don’t typically socialize outside of work other than the very occasional text message. I have very few other Jewish friends and have never attended a Mitzvah reception before. I will be attending the reception in the evening but not the ceremony earlier that day.

Would greatly appreciate any recommendations as it pertains to gift etiquette and/or recommendations for her son. What’s appropriate, what’s not, guidance on gift budget, etc. TIA!