This dress was a present that Samantha made for herself after she went through an entire season without long-sleeved "winter" dresses to wear. She sewed the dress in the Spring, wrapped it up in paper, and gave it to Laura to deliver when Autumn came around in a few months. That way she had a surprise when a winter dress showed up on her doorstep just in time to wear it!
Samantha Parkington's Dresses:
So Samantha is always sewing another dress so she can wear it to proper school, or borrowing one of Rebecca's dresses if she isn't done in time.