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It might be possible, because when HRE died he became germany.. hard to explain

cooro- but if germany was HRE wouldnt he be alot younger then italy? when italy was little him and HRE were the same age, if HRE died and was reborn he would be alot younger then italy wouldnt he..?

It may be the case, but many arguments follow the same reasoning. The character designs for canon child Germany are the same as that of the Holy Roman Empire. Italy was, in addition, already much older than the Holy Roman Empire; Italy possibly could have been born in the BC.