If you didn't specify NO replacements NO substitutions AT ALL from MPC, they probably threw one in that should look similar as an adult. You'll notice they make a statement about replacements based on hatch quantity - I'm guessing their BRs hatch tons and not so many of the others, so it wouldn't surprise me if they did this to lots of people to spread their less prevalent stock over more orders. Yours is the 3-4th post I've seen with a BR thrown in from MPC when they ordered something else.