Both Par and Aly asked how old the pups were... Both Anna and Arthur are around 5 months, but they outweigh Charlie by upwards of 20 lbs. The aggression just started being an issue a couple weeks ago. Believe me, if I could leave them outside during the day, I would, but there's not way when it's over 100 degrees out there!

Yesterday, when we heard the fight we immediately separated them, leaving Charlie and Chloe on one side of devide, and Anna and Arthur on the other.

We're not leaving anyone alone unsupervised, not any more.

The idea about calling a behaviorist might work. We have one who I called about Chloe way back when we first got her. THey charge $50 for the initial consultation, then go from there.

Thanks, Aly and Par for the advice!