What is the chance my 2nd son will have red hair

I have bright red hair my 1st child has red hair. will his lil brother have it too? My husbands mom's hair is a shade of red looks more brown. My brother and I are the only ones who have red hair in my family. Does anyone know the chance of my 2nd son having red hair too? I hope so :)

Hair color is controlled by several genes (at least 5). There are many shades of hair color, and creating a pedigree can be quite complicated.

the site below has a chart that helps explain what is currently understood about red hair inheritance

there is a 50/50 chance, he will have red hair.