Anyone else's twin,

Anyone else twin stay curled up most of the time? Our first one is extremely active. The second, he/she stays curled up. And is upside down lol. My daughter was the same way, so I'm not too worried, but she was extremely active also. This baby was also sucking it's hand so he/she does move around, and yesterday they were both flipping. So I know they do move a bit. Just curious if anyone experienced this. And did they get more active farther along?