Hmm, wondering if I'm handling this ok?
Tiffany can be a bit of a grumpy ar*e. She looks like butter wouldn't melt, and she is a little sweetheart with her cuddles and happy, stumpy tail wiggling dances

She doesn't react to Sasha when Sasha's in her face or pushing her out of the way or jumping all over her. But...
Try and get Tiff out for a wee when it's raining and I have a little

She will stomp to the back door, head down, reds of the eyes showing, body tense, and if Sasha gets in the way Tiff will go for her. It rarely happens, and I just manage it when it arises iykwim. So I'm not overly concerned.
But I wondered, apart from ignoring the behaviour (as I do), is there anything else I could be doing? Or should be doing?