This is exactly the age gap between me and my sisters, when I was born they were 10 and 8.
Obviously the age gap was too wide for us to play together, as such, but they were great big sisters and I think they enjoyed having a much younger sibling. Most of the time! Things like Christmas I suppose it kept the magic going a bit longer having a much younger child around.
In some ways I suppose I also had similar experiences to an only child because a lot of the time I had to amuse myself while they were doing there own thing. Then at others it was a bit like having extra adults around to indulge me! I remember going around everyone in the family to read to me until I virtually knew the book or comic by heart. Maybe one of the reasons I took to reading so quickly. And of course all of their old books and toys were available to me.
My elder sisters both left home in their late teens so my older childhood and teenage was again, a bit like being an only. However it was often handy having these young adults for advise and help. Sometimes they would have me over to stay at weekends which was always a great treat.
I think in later adulthood, since our parents died, we have become closer than we have ever been.
Obviously I can only really give the child's POV, don't know how it was for my parents. One thing though. I can remember sometimes my DM looking back with rose tinted spectacles to when my sisters were little and how good things were then. As a child I felt a bit slighted, why wasn't it as good with me? I suppose my parents were ten years younger then with more energy and having two small children close together was fun. Perhaps it all felt a bit harder second time around...