This is why I asked and replied.I know it's not a welsummer, it's just a mutt
because she had a chipmunk pattern as a chick (maybe part wellsummer??)
IIRC about 20-22 weeks.How old were your brahmas when they started laying? Because I noticed what looked like our buff brahma's feathers in that nesting box, but I thought she was too young to lay
Here's how to tell.....
https://www.backyardchickens.com/articles/who-is-laying-and-who-is-not-butt-check.73309/