Thank you! This chapter did seem kind of "foody" but Ennis holding up his end in that kind of conversation, even if he's still as un-chatty as ever, is a kind of indication of his getting more established in this household, new as it all still is. And what story based in Minnesota could be without at least one
lutefisk reference?
There is a point in grieving for a loved person who's died where you suddenly find yourself thinking about them just as the person you knew -- i.e., some funny remark, shared experience, some little quirk or fault -- and that this kind of reference point, for the first time, has at least temporarily crowded out the loss. It isn't a matter of loving the person less, just that the loss has become a part of your own life rather than an outside force that's derailed it.
I don't know if I'm making that completely clear, but it's at least part of what Jack had in mind when he told Ennis to find a memory of him that he could laugh about.