Is it normal that my boyfriend's sister is so jealous?
My boyfriend's sister is being very strange towards me. We had a dinner last night where guys were assigned to serve girls, he was assigned myself and her and she insisted he serve her first. Our friends were just joking about who he should and she got all serious and was like "He better put down my place first!" and gave him a strong look. When he said he was thankful for me, she gave him a look until he said the same to her. When he smiled in a picture with me, she commented 'why didn't you smile when you took a photo with me?' When he asked her to take a photo of the two of us, she gave him a look. He thinks she's jealous as the two of them are very close. He did serve her first by the way to make her feel better. I'm not the jealous girlfriend type so I didn't exactly mind, but I also feel like it's a bad idea to entertain that jealousy by placating her. I don't want to get between their relationship, I think it's great that they're close but I find it weird that she expects to be treated the same way as me. It's really bothering me.. is this normal?