If they're all loose together? Fifteen hens minimum for two, 20-25 hens is better for keeping the peace. And they won't fight for a long time. Then at about a year to two years they're most likely gonna get really aggressive with one another until one comes out on top and the other becomes a bullied horrible wreck. (In my experience.)
Or you can keep them in a bachelor pad together with NO hens/hen contact at all and they'll chill and live as bachelors together. Or keep them in separate pens with a handful of hens each.
If you only have a "few hens" you might not even have enough for one rooster let alone two so you might wanna consider removing one.