I find that older dogs(especially girls) are not that tolerant of jumpy dogs. They are more likely to correct them or put them in their place. My oldest female(non GSD)has done so with all dogs in my house(I have 5 dogs of my own and 1 foster). They all respect her and back off. If two of the dogs are getting to rough, she steps in before it gets out of hand. It's pretty amazing to watch. I got my female GSD(now two) when my female was 7 and the age difference has helped. Every now and then the GSD will attempt to challenge the older one and I do step in, the older one has earned her respect over the yrs. the female GSD will eventually be in that role and I probably won't get another female for a long time, if ever. The female GSD doesn't put up with bouncing around or no manners. She is falling into that role as the "leader" . The boys don't care, but sometimes I think they annoy the girls on purpose. The girls sit back and watch while the boys goof around. All in all they all get along well and even with changes in temperaments as they get older that isn't changing. The two youngest are boys and both have wonderful temperaments that I foresee staying the same.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD