When my mother wore her house coat, she was wearing a light-weight cotton knee length cover-up over her nightgown. Her house dress was a non-fancy dress for everyday wear at home, while doing housework. She'd change into a regular dress before my dad came home from work or if she were to go out to the grocery store or somewhere.
Leebee, you brought back such nice memories of my Gramma. She wore a house dress every day, but didn't change for dinner. She wore it in the house, to the store, to visit other family members, but it was a house dress.
As she got older, she didn't want to wear anything but the same style house dress that she had worn for years and years. It was very difficult for my Mom to find them for her. They were light-weight cotton and had 2 pockets in front, at the waist. She needed somewhere to put her change purse, ya know. She called it her pocket book.
My one regret about her is that she passed away 4 years before we adopted our kids. She would have enjoyed practicing Russian with me before we left to adopt them and she SO would have enjoyed speaking to them in Russian before they could speak English.