An update to the algorithm for the DNA test I took for my mom's genealogical research prompted this hall of fame subject line in the email she sent me this morning
lol There’s nothing ever mentioned in the film. I have no grounds to refute this. Best I got on Lineage is that both brothers wear those horn necklaces and Mario’s love for his tools came from his Poppa by way of his GrandPoppa. Entirely likely
They're brothers, Mario Mario and Luigi Mario. I assume if one of them is Jewish, so is the other, given their common origin, but if Mario converted (maybe for Peach?) Luigi might remain among the nations.