I have a brother and a sister, both older than me (by seven and ten years respectively).
I used to be closer to my brother when we were younger, but if I'm being honest, that was more because his first wife was very good at making sure he saw a lot of the family and kept in touch etc. We would see them regularly and have a lot of family meals etc at my mum and dad's and so on. When he was single, he was pretty lazy about it, and his second wife was a very, very difficult woman who didn't really want much to do with our family at all. He's single again now and I see him briefly when I visit my parents (at the other end of the country) because lives with them, and we exchange the odd text and Facebook message. I love him dearly and I'm sure he loves me too but we don't see much of each other and he wouldn't make the effort if I didn't, and I can't always be bothered to always do the running. He is what he is - he's great when i do see him and we always have a lovely chat and a great laugh but he's really bad at communication otherwise.
I see my sister a few times a year, sometimes with my parents and occasionally we meet up and do something or do each other a favour or whatever. We have very, very different personalities and sometimes find each other a bit frustrating but we get on well enough to meet up for a meal or something now and again. Again, I love her dearly and I would hope that she loves me too - our relationship is perfectly good, but whether I would say 'close', I'm not sure.
My brother and sister are probably much closer emotionally to each other than I am to either of them, which I think is because they're much closer in age and also have a particular personality trait in common which I think means they empathise with each other a bit more than they do with me. They had both left home by the time I was about 13 or 14, so I felt like an only child throughout my teens really. I feel like they are much more of a unit than I am, like I was an extra that came along when they were the established siblings.
That said, my sister regularly moans about my brother and how selfish and uncommunicative he is.