[BH] Family Recipe is actually more a Household Recipe

I am unsure if this is a bug or an oversight, but I'm reporting it anyway:

The family recipe can only be taught to sims that are part of the same household. They can also be taught to household members that the teacher sim is not related to. They can not be taught to sims your sim is related to but that are not part of the household. 

I had a sim try to teach her adult son who moved out of the home a family recipe and was disappointed that it didn't work (son is unavailable to be picked in "teach family recipe" menu, even when the sims are standing next to each other in front of the fridge). Other family relationship interactions are after all available for sims that do not live together but are related, like the family dynamic from Growing Together and the family keepsake box, or family specific socials like the Family Kiss. 

It is not an age issue, because my sim could teach the recipe to the ghost of her elder father that lives with her. 

Tried a different household that has two married sims and their children living together with a good friend of the parents (no family relationship, just friends and housemates). The non-related household member can teach and be taught family recipes by anyone in the household. 

Seems the way they are coded, family recipes are actually household recipes, they can only be taught to household members, independent of relationship. I find that disappointing. It's nice that I can teach them to all sims in the same household, cool for honorary family members, I like that, but it's sad that it's unavailable for sims that don't live together but are related. Other family interactions are not that limited after all, and for storytelling it would be nice if grandparents could teach recipes to grandchildren without having to live with them, or parents teach them to grown up kids, or when the parents separate and the children live with one parent and visit with the other parent. At its current state, IMO "Family Recipe" is a bit of a misnomer. It is a household recipe, and with the way it's described as something to pass down in your family, it seems like a bug that I can't teach it to all my family members.