Anonymous“so you can have two pronouns back to back?”
Well, you could say "... writing about the man whom I admire", where "man" is a noun and "whom" is a relative pronoun, and I don't see any fundamental difference with "someone" being a pronoun in "... someone whom we admire".
Anonymous“is that considered a pronoun phrase?”
It seems reasonable to me to call "... someone whom we admire" a pronoun phrase, but I'm not 100 sure about the terminology here.