My mother wants to stay!

Victoria • I`m a 34 year old married woman! I`ve been with my hubby for 10 years and we have a beautiful 5 year old little girl and a 2 year old little girl! We’re TTC #3.
I just reached my third trimester and I'm trying to figure out last minute details of everything (meal planning for the first few weeks, etc) my mom wants to actually come STAY with me for at least a week..I'm not extremely close to my mom and I honestly have no desire to have someone come stay with me during that time! I mean she lives 20 minutes away...I don't mind her helping me during the day if I need it, but I don't want her staying here. I want it to be just my husband and me and my new baby! How do I tell her no thank you?! She is so excited about her first grandchild but she's never dealt with a baby before (I was adopted when I was 12). I'm pretty sure she's going to drive me and my husband nuts....