These are really easy to make and can be made a number of different ways. Ok I am going to break them down more and include the pictures again below so you don't have to keep scrolling up and down to see what I am talking about.
This one was made using a onesie from a pack I had. I just picked out some fabric that I thought matched the family and the tastes I felt would go well. This dress was made for a little girl named Gibson. Her daddy is a talented amateur guitarist that plays at the campfire gatherings we have often. So guitar prints were used on a number of things I made for her. I took the onesie right at the leg holes and cut it across to make it into a tee. I then took the fabric and measure it around the bottom of the now-cut onesie and gave it another front length so I could give it some extra room to gather it a bit. I then took the cut guitar print fabric to the sewing machine and sewed up the side to create a tube, then turned the bottom up to create a casing in which to pull ribbon through to make it more of a gown, so the feet could be kept up in the fabric but loosened for diaper changes (also because I thought it would be a cute touch. Once I finished the casing and added the ribbon. Then I lined up the top part of the fabric wrong side out to match up with the bottom edge of the onesie/tee, pinned it into place and attached it using my serger. You could use a zigzag stitch if you don't have a serger. It was super quick and lots of fun.
This pirate girl one was made from a black infant tee I purchased at Hobby Lobby. I happened across this fabric at walmart on the $1/yd rack when they were fasing fabric out. It is kind of hard to make out in the picture, sorry it was taken with my cell phone and is a little washed out. I took it right before putting it into a gift bag for a baby shower. With this one, I measured the fabric to the shirt the same way, lots of give, so extra fabric used on this one was used to gather it at the waist area. So I gathered the waist area first and then hemmed the bottom edge. I sewed up the side to make it a tube, then pinned the gathered edge to the bottom hem of the tee and serged it into place. I felt it needed a little something else so I had a pink rhinestone girl pirate iron-on that I put into the middle of the black tee for a little girly bling.
