With the usual black sex links as chicks the males have a white head spot and the girls do not (they are bred so they can be told apart at hatch by color) ... white on the belly or wing tips doesn't matter depends on the cross used... and the males will grow up to be barred birds and the girls black with some red usually... Cackle happens to have pictures/video of male and female bsl chicks http://www.cacklehatchery.com/blacksexlinkpage.html
How are his feet different? Could the barred one be a different breed, did they give you a free chick with the order or something maybe? You could try posting in the What Breed/Gender forum, they are too young to tell sex by combs etc yet, but if you think the other one is a different breed... https://www.backyardchickens.com/f/15/what-breed-or-gender-is-this
How are his feet different? Could the barred one be a different breed, did they give you a free chick with the order or something maybe? You could try posting in the What Breed/Gender forum, they are too young to tell sex by combs etc yet, but if you think the other one is a different breed... https://www.backyardchickens.com/f/15/what-breed-or-gender-is-this