What age is the youngest your dc could (safely) share a bed?!

[WriggleJiggle]

Please feel free to read either version:

SHORT VERSION
When's the soonest I can throw dd1 and dd2 in bed together?

THE LONG VERSION
dd1 (2ys old) sleeps happily in her cot.
dd2 (6 months old) has accidentally become a co-sleeper. I quite like having her in with us, but at the same time, co-sleeping was never the intention and I'm think I'll be quite happy to get my bed back again.

So I thought, at some stage, when it comes to reclaiming my bed, how can I do it most gently? Would it be gentlest to put dd1 and dd2 in bed together? Or is that stupid?

I'm thinking along the lines of changing things when dd2 is 1yr, so dd1 would be 2 1/2 yrs old.

Would it be safe? Can toddlers share beds?

Is my brain really really sleep deprived, and does it show?

yes - my twin cousins shared a double bed from about 1ish.

I know people with twins who have done it from birth, but having an 18 month age gap made me a little more cautious.

oh yes they did sleep together from birth but in a cot until they were one.