Why is my speech impediment worse around my mom?

Why is my speech impediment worse around my mom? So I have a speech impediment, I wouldn’t say it’s too bad but I do have some word blocks and stutters from time to time, it’s moderate enough to live a semi normal life. Everyone else I talk to is good but whenever I talk to my mom my stutter because progressively worse, I can barely get a word out so our talks are relatively short.Mind you I do have some mild anxiety and I don’t know if this is a cause of it