The search for loose-fitting nightgowns that are 100% cotton is a fruitless effort in the USA, what with our child protection safety laws. They are all treated with fire retardants that are proven to cause long-term health problems. So, what's a sewing mama to do? Make her own! *
With that in mind, I bought some lovely light-weight pink floral fabric from a sweet sewing mama on Facebook and decided to use Modkid Penny as my pattern. The fabric turned out to be a nice weight but does not have a ton of stretch. Still, I went ahead and used it for the whole nightgown rather than spend lots of time and money searching down something with more stretch to use as the binding. Frankly, binding drives me a bit nuts and since my own kids don't care, I just went ahead.
Here is the finished result. In less than one hour, from cutting out to finished product, including serging and finishing all seams, we have one cute nightie and one happy girl.
I highly recommend Modkid Penny. It is a great pattern, very simple to use, nice instructions. Be sure to trace your pattern pieces so you don't have to cut into the paper pattern and you can make many sizes. Penny have four views to it and several more options: short sleeve, long sleeve, top, dress, contrasting sleeves or bodice, and ruffled hem. A very useful pattern indeed!
* I take full responsibility for any fire liability for my child alone. You are on your own.