One good egg?

I'm incubating six Cream Legbar eggs. This is the first time I've done this and it's so exciting for us. We definitely have one good egg that's viable as of right now (day 9). I know things may change and we may have none, or we may have more than one hatch when all is said and done. I just have a feeling this might be the only one and I want to be prepared if that's the case.

My question is, what happens if only one hatches and survives?

Can you raise a single chick? Well, I guess I know you CAN, but is it stressful for the chick to be alone? I have 7 hens but obviously there'd be a significant amount of time before the chick could be integrated into the flock.

It'd be difficult, but probably not impossible, to get another chick or two locally around the same time this one hatches but I'd like to not do that unless it's necessary. And at that age, how much difference does a few days in age make? A week? Etc...

Just looking for feedback and opinions. If anyone's been here before, please chime in!

Thanks!