Let me expand my original post.
Sam Muise (b. Dec 1867) and Sylvia Saulnier (b. Feb 1867) had 5 children:
- Jannett Muise (b. May 1888)
- William Muise (b. March 1889)
- Nettie Muise (b. Feb 1892)
- Thomas Muise (b. Feb 1894)
- Lena Muise (b. Oct 1895)
So your grandmother's father, Thomas Muise, had 3 sisters and 1 brother. The information about William Muise in my original post was Thomas' brother.