The last conversation was in 2021, the year Qianqian was born.
Zhou Zining: Shuxian, I want to move to Rongcheng City and settle there.
Bo Shuxian: What's wrong?
Zhou Zining: I just miss Rongcheng City; after all, that's where I went to university. The Capital City is great, but it lacks a lot of people I care about.
Bo Shuxian: Don't you have me? And there's Grandpa and the second grandma. You rarely visit the Bo Residence, and if you don't like it there, we can always live outside. Besides, my work is more convenient in the Capital City.
The second grandma was the concubine married by Old Master Bo.
In that era, monogamy wasn't strictly required. Besides Old Lady Bo, the legitimate wife, the old man took a few more concubines.
If one were to be detailed, Bo Shuxian's father was born to one of the concubines.