Canvas is traditionally white. You are not traditional. - Even if the parental bit is iffy, the non-traditional unicorn made sense to me, meaning this clue DID point to Sacre in my mind
Or maybe you are? Blood runs thicker than water. - I'd pass this on all three of Whit's clues here. It's a lovely loaded line.
Do you ever wonder what would become of you? - Fluff.
Your name is Robert. - I get Robert Sacre when I google Sacre.