Tap pants are these old-school underwear, loose in the legs, worn at the natural waist.
Google patent search has at least one from the 1939 available.
(The gray blob after "Here's a" is a link to the patent. Click it. Someday I will figure out how to add a background color to link text w/out having to mess with CSS. But not today.)
Here's a link to patent.
This pattern appealed to me because it was just a handful of simple shapes - deliberately designed to be made from small pieces of fabric.
I used more of the silk twill I have - it is not too bad to sew, but the twill structure makes it a little springy and it does not hold a crease too well.
I used a single snap at the waist to close (no elastic in these pants).
To derive the pattern, I made the assumption (wrong or not) that the pattern piece sketches included with the patent document were to scale. Certainly, the finished product is plausible, except for the crotch piece. That is very long and looks like the pants might ride up something fierce.
I suppose I could always take a tuck in it later.
I enlarged the sketch until the waist was the right size for The Dolls.
I may need to play with the proportions of the pattern pieces to fit The Dolls' less than ample posteriors. I believe the leg openings are too wide and the crotch piece is too long.
I sewed the side front pieces to the front triangle, and the side back pieces to the back triangle, then attached the short sides of the crotch piece to the short extensions of the side front and back pieces. Then I did the side seams, and finished the waist and leg openings.
It might work better to attach the side fronts and back to the crotch piece, then turn under the allowances of the front and rear triangles, and apply them to the side/crotch assembly. I shall experiment further.
This first pair, I believe, will fit the smaller of The Dolls. At least in the waist.
Yes, eventually I will name The Dolls: I have gotten as far as looking up popular baby names from 1921 and 1927.