I took my bloomer/diaper cover pattern (from Ottobre 3/2009) and lengthened the legs by two inches, added lace along the hem, and instead of elastic for the legs, did elastic shirring, and, voila! Bloomers:
By the time babies get to size 18 months (and some 12 month sizes) the dresses don't always come with bloomers. But it is still nice to have something to cover the diaper. I thought I'd make a pair in white so that they would go with everything.
I love how they turned out but I think I'll also make a plain pair so that if I don't want the lace showing under the dress, I'll have something simple.