I will admit, I really have absolutely no idea why Sydney and Darby are so compatible. Not because of Darby, but because of my little "angel" Sydney. Syd desperately wants someone to play with her, but she plays SO rough, the other dogs just cringe and run away after a body slam or two. And Syd is *very* persnickety about play. "OK, now you will run to the left corner, then I'll chase you and knock you over, and then you get up and chase me back to the other side of the yard, and then you spin around and I'll tackle you." She organizes and runs the show when it comes to play time. And oh, if you DARE to not follow Syd's rules of play, well, then there is heck to pay.
One of the KEY rules to Sydney play is "You will not flip the Sydney on her back." If anyone dares to play and Syd flips over for some reason, she will get up as her evil twin and grab whoever it is by the face and tell them they'd better not do that EVER again.
In nutshell, Syd has some play issues.
1. She plays WAY too rough for the other dogs in the house.
2. She must make all the rules, and those who don't follow will catch heck.
3. She isn't really much on other girls. Period.
4. No flipping Syd on her back, EVER.
5. No flipping Syd on her back, EVER.
6. No flipping Syd on her back, EVER.
So, when Darby came along, I was very watchful and never let Syd and Darby into direct contact for quite a while. Darby is so amicable I was afraid she would walk into a Sydney Play Trap and get herself chewed up and spit out. So we did gradual introduction, through the fence of the dog yard, then with Darby on leash with me and Syd running around, then both loose and me with the rake (I felt like I was at a herding lesson), and then finally I let them play for a few minutes at a time, then put someone in the dog yard so that every session ended on a good note. I wasn't sure how Syd would be because Darby is a girl, but I was hoping that maybe being a puppy would work in Darby's favor.
Nowadays, I can put Syd and Darby outside together for hours, and there are no problems. Syd is so happy, and Darby is smart enough to handle Syd. When Syd gets really wound up, Darby will still engage in play, but she uses the A-frame, or under the deck to put some space between them for just a split second, then she pounces out and tackles Syd. Yes, you heard it right, Darby can tackle Syd. The first time I saw Syd flip over on her back while playing with Darby, I sucked in a breath and prepared to go save Darby from a real discipline session. But when Darby let Syd get up (yes, you read that right), Syd just did a play bow and took off running for another chase. I'm sure my heart stopped beating for a moment.
I even have it on video, because those who know Syd best would never, ever believe that she and Darby are the unlikely best friends, and this clip even catches (gasp) Syd, flipped on her back! I wouldn't believe it either, if I didn't see it myself every day!