two sister GSD

Question
I was reading that it is not recommended to have two female GSD but to have one female and one male. We recently purchased one female and are seriously thinking about purchasing the sister. As they grow older, will they become agressive toward each other? Will getting them fixed help?  

Answer
Hi Mary Ann,  Yes I do not recommend that you purchase the sister, fixed or not, odds are as they mature they will start to not get along.  It is a problem that has been increasing in GSDs over the past decade or so.  You will probably have them fighting amongst themselves by 2 years of age.  Hope this helps,

Dawn