Boston Terrier and Chihuahua

by Ana GonzaleZ
(Laredo tx)

I have a 1 1/2 yr old female chihuahua and my BT female and her have been like besties ever since they first met - well, until a week ago. My BT has been very aggressive towards my chihuahua. Could it be that my BT is pregnant? I really don't like this because I have to separate them and I love them both. But, suddenly they're not getting along. Can you please help me with the question? :-(