How to delete a number off my iphone's link?

Okay so i'm not too sure of this but i recently got a iphone 5s. I've been using the 4s. The 5s was given to me by my mom since she no longer uses it. When she gave me the phone, she had her own sim card in it. After i wiped out the data on the 5s, i logged into my own apple account. After the new phone set up was done, something popped up saying something like " would you like to connect this number with So and So's iphone and ipad?" without me realizing it, i accepted. So now when i get a text, the 5s, my 4s, and ipad all receives the text. How do i take off my moms number from being connect to all my other devices?

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