In RoB Twins mentioned cousin Lars already, which means that in RttE they used Lars number 2 to avoid possible confusion that Twins are related to Grimmborns.
Which and let's be honest there would be freakin funny XD
Viggo: No, it certainly would not....
Chilli it, Viggy.
Viggo: Don't call me that.
Viggy?
Wiggly Viggy?
Wiggle wiggly Vigg-
Viggo: ENOUGH!!!