Here's hoping that Rachel doesn't pop out an extra-big baby this time. I've done the body of the cardigan and it is about 16 inches around which according to what I can find on the internet is about the right size for a full-term newborn baby. So I figure her kid will have about six weeks to poop all over it before it grows into the next size.
I've only spent a couple of days knitting it, so I'm not too stressed if it only gets a couple of months wear. I'm sure to knit up something else by then.
When my friends had their first rounds of babies I made everything way too big - jumpers that they couldn't wear until they were 12-18 months old. I didn't want them to grow out of the clothes too soon.
This time around I am actually trying to knit something that will be usable within the first year.