Patterns that give finished measurements are awesome. It is such a simple thing, but it can make a world of difference. For instance, I made a Winter Bonnet from the free tutorial and pattern at the Purl Bee that only told what size the rectangles would be.
The 6 month size fits my 8 month old like this
(Big Brother had to hold the wiggly A still for a photo)
and my 3 year and 8 month old like this
(Our photo options are smirking or sulking these days as he is 3 going on 17.)
I really like the pattern, but the sizing is a bit disappointing. I haven’t been able to bring myself to make another yet. On the plus side I do like the result and I can feel assured that if will still fit A next year.