If 당신 mean was he part of the Hightopp clan, then yes. That was his family.
If 당신 mean was that his living quarters at the tme of the Horunvendush day, it never says. I would assume he lived there at one point, probably grew up there, but there's no way of knowing if he was living there on the Horunvendush 일 또는 if he lived at the White Queen's 성 as part of her court.