I was worried too when we just had Wylie, but started thinking about getting another. We got Marcel when Wylie was around 2 yrs old. Wylie definitely was nervous...he became extra needy and clingy, which was just fine - we reassured him and made sure we treated him like the alpha dog (and we still do). Being a puppy, Marcel was clueless to all of this - so he just dug right in and had no hesitation...which I think was great for Wylie in the long run. I'd say it took about 3-4 weeks for Wylie's clingy-ness to go away.
A few years later, we got Pfeiffer (a girl) and both the boys were just all "okay, cool, no biggie" and just accepted her immediately like it was no fur off their backs. She is now one of the boys
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So, even if your kiddo acts a bit funny at first - don't worry TOO much (I won't say don't worry at all, bc I know you will)...it'll be fine, just takes time. Let us know when you get your second one! Oh, and your THIRD one too
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