Is this normal for a 2 dog family

[I~love~pie]

things have been going well, since we've moved. but I have noticed something different with our older dog. (shes 3)
if we put Daisy (almost 2yrs) outside without our other dog, when we let her back in it seems as if our older dog is scolding her. she will either bark or growl at her. she doesnt bite her and this DOESNT happen every time. maybe 3 times out of 10.
should I just chop this up to them being dogs.
They have been playing together well, they really act like sisters. And if they do something they shouldnt be doing they do listen to us and stop right away.

I just dont know if I should let it go, or do something about it.

[Doodlebugsmom]

My older, dominant dog, Maggie, did this very thing with our younger dog, Hannah. They were 5 years apart in age. (Hannah died in July). Maggie would scold her if she got in her way when they were at the door barking at passersby. I always attributed it to her being overly excited or not wanting Hannah to get the upper-hand on protecting the house. She never would've hurt her, they were the best buddies, but I just assumed it was Maggie asserting her dominant position. It's kind of funny because Maggie weighs about 23 pounds and Hannah was a 75 pounder. Hannah was the sweetest thing. I miss her so much. She would've done anything Maggie wanted. She gladly let Maggie take the dominant role.