We have Peanut, born Nov. 1, 2012. Then three days after we got Peanut, we got Nemo, born Jan. 1, 2013. We got two knowing about separation anxiety, and it was the best thing we could have ever done with these two. We got Peanut at 16 weeks, Nemo at 8, and they've been attached since the beginning. We have a deposit down on our third, born June 8, 2013, and we get to bring her home at 8 weeks - August 8th.
Once you get past the stubborness, you won't ever want another breed of dog ;P