I've noticed my cat Azula is hissing at her sister Divina a lot more than usual lately. Of course, cats play with each other and sometimes hiss but they are twin sisters, they've never been separated from each other in the 4 years they've been alive, they've never had problems.
I got them from a woman on Facebook in Cali about 9 months ago. The lady that I got my cats from had said she was giving them away because she's always traveling for months, so she wanted to give them to someone that could give them more time and affection. I got them and moved away from Cali to Washington about 2 months after that, the traveling was perfect.
The last 6-7 months they've been fine, playing with each other just being kitties. I'd say I'm closer with Azula, she's always laying on me or is on my back, sleeping under my covers, looking at me while meowing and I meow back like it's a conversation that goes on for a while. Divina is also a very verbal cat, loves to bet pet and meowed at but isn't all over me like Azula is (like sleeping under my covers.)
Out of nowhere, Azula has started being rude to her sister and hissing every single time she's close to her. I'm usually home, but I got out with friends and come home at night. I also stay at my boyfriend's place for a week sometimes, usually only 4 days, out of every 2 to 3 weeks, but I don't think that is what's wrong, because when I am gone, which has never been longer than a week or so, my friends and family check up on them in my room, feed them and play with them a lot.
When Azula hisses at Divina now I tell her in a stern voice "No don't be mean to her." not yelling, but it makes me worried because I don't want Azula to hurt her. After Azula is rude to Divina I give Azula her space and comfort Divina because I feel she feels that she's getting neglected by her sister.
Can you help me find out what is going on between my cats?