Hi all,
I figured out the comments issue. I downloaded Google chrome and signed in again using Heather's info. This worked.
I think what happened was when I signed in using Firefox, it was only temporarily. Each time I clicked "sign in" I got to listing my blog and thought I was signed in. There was no place on the blog page to allow me to sign in with Heather's info.

I'm still not sure how I could change the Firefox setup on Blogger, but did figure a way around it.
Thanks all for your possible solutions. They helped me find the way!
Jo Noble