Hi!
First off I just want to tell you that you have two very beautiful dogs!
I think I would suggest getting a male puppy next. It looks like your two girls get along just fine but I think thats because your Czech Wolfdog pup grew up with the older female being dominant, kinda like a mother figure, but from what I've been told, female Wolfdogs normally don't get along to well so introducing a new female might make your 10 month old feel imtimadated and turn against the new pup.
I have a 2 year old male Czech Wolfdog and a 5 year old female German Shepherd dog and they get along great and keep each other in line.
[Two dogs is all I can handle!] :P
But if you're set on another girl, I'm sure with proper training and patience they'll all get along just fine.
Have fun with your new puppy!
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