Where do they sell clothes for morbidly obese guests?

I’m not trolling, I’m just going anonymous, so as to protect my privacy and that of my friends.

I’m seeing someone I really like. If we get married in a few years, I have three best friends that I want to be my bridesmaids and maid of honour. The two who’d be the bridesmaids already have their own outfits.

The one who’d be my maid of honour is dirt poor and morbidly obese and can’t afford decent clothes; so we agreed that I’d help her buy some smart casual or formal clothes. However, I’m really not trying to be funny when I say this, so please excuse me; but most stores don’t stock clothes in her size. She’s almost too fat to walk without a walking frame.

Could anyone please suggest some ideas for real places that sell nice clothes for morbidly obese people? I think they too, should be able to look as nice as they can.

Updates
4 mo
And yes this is a real question. People are getting bigger and fatter these days, where I live and many of my closest friends are morbidly obese. I want to help her look nice.
Where do they sell clothes for morbidly obese guests?
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