(a) My father is a doctor.
Watashi no chichi wa isha da/desu.
(b)Ms. Sada's father is also a doctor.
Sada-san no otōsan mo isha da/desu.
In Japanese, the terms to address or refer to one's own family members differ to those used in reference to someone else's family members. Referring to one's own father, the humble form of chichi is used; in reference to someone else's father the honorific form of o-tō-san is used. When addressing one's own father however, the honorific o-tō-san is used.
「There will be a list of all the terms for family members either that of your own, or your friends, and when to use and what, that will be put up in the near future, please look forward to it!」
Watashi no ani wa kōmuindesu. Kachō no o-nī-san mo kōmin desu.
My older brother is a civil servant. The section chief's older brother is also a civil servant.
Musuko wa daigakusei desu. Tagaki sensei no musuko-san mo daigakusei desu.
My son is a college student. Professor Tagaki's son is also a college student.
Kanai wa hisho ja nai. Hiru-san no oku-san mo hisho ja nai.
My wife isn't a secretary. Mr Hill's wife isn't either.
Sofu wa seijika de wa nai. Tomodachi no ojīsan mo seijika de wa nai.
My grandfather isn't a politician. My friend's grandfather isn't, either.
Hope you find this useful, and hope to see you again!
°˖ ✧◝(○ ヮ ○)◜✧˖ ° こゆうきあいはら °˖ ✧◝(○ ヮ ○)◜✧˖ °