Here she is wearing it. It is very hard to photograph a baby in a way that shows the garment well! She was much more interested in playing with the plastic coat hanger I'd removed for the photos, and this was the best I could do before she lost the plot! The collar sits out a bit when she's wearing it, but I think will settle down once she's worn it once or twice.
Here's what it looks like without her in it. I made one or two minor changes from the pattern. I made the bodice section 2cm longer, because I thought it might look a bit bulky if the fullness began at her armpit, and I put buttons down the whole front so that it stays closed over her tummy (and because I had four buttons, and I really like them). I also made the lining in one piece so it's less bulky.
It's hard to tell in the photo, but to make the lining sit nicely I sewed it to the armhole seam of the outer shell of the coat. This makes the sleeves sit better, and stops the lining shifting around. In my own coat I sewed the lining of the body to the seam, then slip stitched the sleeve linings on by hand, but this is a baby coat. I want her to spend more time wearing it than I spent making it!
This rather fuzzy photo is how I drafted the lining piece. The dotted lines are the original cutting lines and the solid line the new cutting line. I did have to trim a chunk off the bottom when I sewed it in, but quite a bit of that was due to the bulk of the fabric.
It took me a couple of days worth of naps to make this, but most of that was due to thinking about how best to make the changes I wanted to make.