Eliza,
I have two boys who are 1/2 Siamese and 1/2 tuxedo. My sister came to visit the other day and Mikey (the ruler of all the land) sat at the top of the stairs where it's nice and echo-y and keep yelling "Hawwhoa?" I'd reply "hello" and he'd call back to me "Hawwhoa". But every time my sister said hello he would ignore her. I think it's because he was mad she couldn't pet him (she's seriously allergic) so he was giving her the silent treatment.