Natalie, It's best you take your daughter (unless you've already done so) to an astro supply shop and get her to stand next to a 10" dob. I think the sheer size and weight will be overwhelming for her. But you would be the best judge of that of course.
But I'm really coming from the point of view if she has to move the scope around the yard to view things (move to dodge trees etc). That's where the 10" is going to be an issue I think. Even if it's on wheels.
Both my 6" and 10" have and had wheels attached to them. Even with the wheels, going over uneven grass etc, its a bit heavy/wobbly and awkward. The guys might actually laugh at me on here when I say this, but to be perfectly honest, with my 10", I fear I'm going to get pinned down underneath it If I'm not careful. Often, I've had to put my body up against it, holding the tube for support at the top whilst getting it out from being stuck on uneven ground, ledges etc. After 9 months of owning it, I'm now starting to get comfortable with how much I can tilt it before I go
*splat* under it.
Putting wheels on a 10" was a completely new ball game compared to the 6". As the base and tube is much bigger, it demands bigger wheels with better movement. My setup for the 10" wheels are- 2 larger ones and 2 small castor wheels. The castor wheels help to aim the scopes direction. They are attached to a frame under the base. Not a solid frame as this would make the scope even heavier for me, but instead have used narrow long pieces of wood. Hope that makes sense. The larger wheels to get are the pneumatic type. Bunnings sell trolleys for around $20- the tyres on them are brilliant. They will be the ones going on my base replacing my current ones I have (which give no cushioning over bumps).
I tried the scope on the trolley in the shop before I bought the scope- just wasn't working for me. It made an already big and heavy scope into even more of a monster with the trolley. Everyone in the shop agreed - I was dwarfed by it all, and my frame just wasn't balancing it very well,
*splat* was going to be inevitable. Perhaps the akwardness of the trolley was just me, who knows, but certainly worth checking into for someone with a small frame like me.
To give you a better idea of the size of a 10" scope against my frame, here is a pic (refer to post no# 30 and click on the image). Now remember, I said before my height is 5ft 5".(and a half!)
You will see in this image, the Saxon (and Skywatcher) have long handles (used for tension adjustment) attached to the top of the base. This is what I use to pull the scope around the yard with on the wheels. Brilliant! I yank it everywhere.
http://www.iceinspace.com.au/forum/s...?t=901&page=30
I got used to lugging around a 6" before even contemplating the 10". And I can tell you, I was very nervous for quite some time handling the 10". If you were leaving your daughter outside alone with the scope, maybe you might have a better peace of mind with an 8" (?) you will be the best judge of what's do-able. If she doesn't have to move the scope around to get the best views and it just sits there on the same patch of grass the whole night - go for it.
Just make sure the base will fit on the back seat. It won't fit into the boot of a large car (I have one). Tube goes in the boot, diagonally.
Carefully consider the 10", and don't rule it out completely though.
If you were to start with an 8", when she gets older, then you would upgrade to a 12". Something to really look forward to. Jen here, has just bought herself a 12" collapsible. So it's handle-able - just!
She went from a 6" too. She still hasn't gotten over the awe factor from the big jump- don't think she's slept in the last two months.
Dobs give the best apperture for price for visual observing. Either size, you definitely won't be sorry. The views that I got through my 6" were just incredible. Going from a 6" to a 10" was quite noticable. Just as it would be going from an 8" to a 12". Generally the two steps up is what I've come to understand the jump size is to take. Don't even think of upgrading to a 14"- you'll need a truck.
12" bottoms out at about the practical size
Even with a 6", you'll see nebulas, galaxies, globs, everything. A dark site will also give you better views than from suburbia- it's like throwing on an extra 2" of aperture.
And I'm going to yell out to all the guys here that rule only by aperture saying bigger is better and tell them to pull their heads in, because sometimes it comes down to sheer practicality.
http://www.iceinspace.com.au/forum/....s/tongue05.gif
Don't confuse yourself with eyepieces yet. Not even until you've had the scope a few months at least. But keep that extra money for things you will need: eyepieces, filters, barlow, eye piece boxes, maps, books, software, etc etc etc. Premium widefield eps start at close to $300 (I think Panoptics start around $270). So that gives you an idea price wise what to expect if you go down the premium ep path.
Do bear in mind though, that the 10" dobs have a faster focal ratio and therefore, will have an impact on the edge performance of many eyepieces. I have a 15mm Orion Expanse and the whole eyepiece is useless now, and I spent $100 on it. All the stars are blurry.
Slower scopes are more forgiving- I didn't really have much of an issue with the 6"- my 15mm worked beautifully. You shouldn't really have a problem with the 8" either. Just once you go under f/5, seems to create some problems.
Hope this helps Natalie.
I think I need a cuppa now. 
We're very much ready for the Astronomers curse but figure it will give us a good chance to learn how to use the thing!
