@LibraryGirl IMO Jew by birth is Jewish if they identify as such. They may want a conversion-like course to familiarize themselves with practice and things like that though. Mainly to help them become comfortable with Jewish faith and customs. Just my two cents as a conservative Jew.
In response to me asking how many cheeses are in the mac and cheese, @IzzyBFriedman just ladled in a gigantic chunk of Boursin and said “don’t worry about it.” I counted six, bare minimum.