I have often heard from my friends how they have a hard time finding modest clothes for their growing girls and/or training their girls and boys in Modesty. So, this one is dedicated to all the baby mamas out there looking for modest options.
You can find all the below items and more at The Muslim Baby. They carry clothes up to the age of 8 years old.
The following options are from Sitrah. They carry up to size 8.
The below options are from Al Moultazimoun
Islamic Design House