Be the Leader Romper Hack

I am a sucker for baby rompers! Now that summer and warmer weather is approaching, I’m all about romper sewing! Today I wanted to share with you a quick hack to turn the Be the Leader into a bummies style romper with an elastic casing waist by mashing it with the Cape Cod.

Here is what we’re going to end up with…


You will need:

1. Be the Leader & Cape Cod patterns
2. 3/8” elastic
3. ¼” elastic
4. Interfacing (or a woven/fleece scrap)
5. Snaps

First things first, let’s get our pieces cut!

From the Be the Leader pattern, we are going to cut the following:

1. Flounce (if you want one of course!)
2. 2 sleeves (I extended mine about 1.25” just to make them more elbow length so that they would stick out below the flounce)
3. Front bodice (this one I altered, see below)
4. Back bodice (this one I altered, see below)

From the Cape Cod swim pattern, we are going to cut the following:

1. Front bottom (this one I altered, see below)
2. Back bottom (this one I altered, see below)

To get the Front & Back bodice pieces, I just used the pattern piece according to my little lady’s chest measurement, but I extended it about 1.5” from the crop top cut line in order to create room for the waist casing. I cut two pieces extended to the fold line shown in the picture below:

To get the front & back bottom pieces, I used the Cape Cod pieces, but made some adjustments. Because swim suits have negative ease and I wanted a little more space in the romper, I sized up from 9-12 mo size to the 2T. For the back piece, I also added a little extra to the bum (see the picture below). When cutting the front piece I sized up to the 2T but did not add extra ease. Make sure that the side seams are the same length when you cut these pieces (so the side that is not cut on the fold for both pieces should measure the same).


Now that we have our pieces, sew the bodice pieces together according to the pattern (front bodice, back bodice & sleeves) and the bottoms (front bottom & back bottoms pieces at the side seams). This is what you will have:


Now you want to flip the bottoms inside out and place the bodice inside the bottoms piece so that the right sides of the fabrics are together and the raw edges of the waist on both pieces match up. Like this:


Sew a casing all the way around ¾” away from the edge.


Now flip the garment right side out and press the seam you just created up towards the bodice. Sew the other seam for the waist casing all the way around ½” away from the seam, leaving a 1” space so that you can insert the waist elastic. This is what it will look like:


Flip the garment back inside out and thread your waist elastic through the casing using the 1” opening you left in the last step.


Then close that 1” hole! At this point I went ahead and finished the bodice part according to the pattern instructions (so hemmed the sleeves, and added the flounce).

To finish the romper part, you have quite a few options. If you don’t want to deal with snaps or any kind of closure and would prefer to just take it on and off using the shoulder opening, you can sew the crotch seam together and add either bands or elastic (my preference is ¼” elastic for the legs). If you prefer the snap opening (which is my preference although it’s a little more effort!), here is how I did it…



With the garment right side out, create a casing for each leg by folding the fabric inside the leg opening and stitching 3/8” from the fold. You can also use bias tape to create a binding if you prefer that method! Then thread the ¼” elastic through the openings and stitch both ends to secure. Next, for the front piece of the romper, I just added a small piece of interfacing, folded up the bottom ½” to the wrong side, and stitched. To finish the bottom piece, I created a little snap placket by cutting a piece 2” by the width of the crotch, folded the short ends to the wrong side of the fabric, and then folded it in half lengthwise.

I sewed that to the bottom crotch and voila! We now have places to attach snaps for both the front and the back! Attach your snaps and enjoy your beautiful garment!


Written by: Tammie Schaefer
Patterns: Be the Leader & Cape Cod Swimsuit
Fabric: Sew Creative