I have a question. And I hope it’s not rude or insensitive

But when women of color get their hair done and things like that. Can you still wash it? With Sewn in extensions? Because I know when my friends wash their hair after it goes back to being naturally curly and fluffy unless they treat it. Or get it done again. I love it. But do you get your hair done weekly to keep the curls away and to keep root growth from showing(the same as me getting my hair dyed and colored) Is there a process? Sorry if this was rude at all I’m just curious!!