We just rescued 3 horses and the owner is coming to get them by the beginning of November. Star my 15 year old quarter horse keeps running at them (she was on the opposite side of the field and randomly trot/cantered at them then bit them) She has done it twice already, we don't know their ages but were pretty sure there all mares. its 1 white, 1 buckskin, and 1 chestnut.

How can i stop this and why is she doing it? Thanks
How can i stop this and why is she doing it? Thanks