It's really striking how many of the episodes this season involved family members of the crew, many of them previously unseen:
Homeward (Worf's brother*)
Sub Rosa (Beverly's grandmother*)
*Characters never seen / mentioned before
If I recall correctly, Worf does mention his foster brother earlier in TNG, it could have even been a season 1 episode. It was a line of dialogue describing life with his adoptive family, so technically this person was mentioned previous to his appearance in "Homeward". Regarding Beverly's grandmother, I also recall that she was mentioned in several instances early on, whether it was a recipe or something about what Beverly learned from her... possibly in "Arsenal of Freedom"?