I would say morning tea - about 10ish until noon would be a good time (it is when we try to do stuff). Sophie is just 1 and she is still having 2 sleeps - 8.30am to 10ish and 1 - 3.
As lilfatty said, I would baby proof too. If the boys are rolling/crawling they will be into EVERYTHING

. Sophie is very curious!. One of her favorite things is our poor dogs water dish - great fun for water play (it is now out on the porch, dog not too impressed!). Some children are starting to pull up at 8 months so that can add more stress too.
I am off to Auckland with my 2 on Wednesday and I will be putting Sophie in a sling so that I don't have to carry her - it means that I can be hands free and not worry about where she has crawled off too! I found that it was good to have a sling/pack even when I just had Amy - they get very heavy after a bit and they wriggle so much.