Node.js - is there any way to guarantee the order here?

through-stream-order.js

var stream = require('readable-stream');
var Transform = stream.Transform;

function Logger() {
  Transform.call(this);
}
Logger.prototype = Object.create(Transform.prototype);
Logger.prototype._transform = function(chunk, encoding, done) {
  done(null, chunk);
};
Logger.prototype.log = function(message) {
  this.push(message + '\n');
};

var a = new Logger();
a.pipe(process.stdout);

var b = new Logger();
b.pipe(a);

a.log('order: 1, stream: a');
b.log('order: 2, stream: b');
a.log('order: 3, stream: a');
b.log('order: 4, stream: b');

// logs:
// order: 1, stream: a
// order: 3, stream: a
// order: 2, stream: b
// order: 4, stream: b