looking for my half brother

My mother just told me last year that she had a son in Las Vegas Nevada in 1955 and put him up for adoption. She was 13 years old and her name is Catherine May Stewart. Her birth name is Catherine May Cowell. Her stepfather adopted her I just dont know which name she had when she had this little boy. If any of this information matches the information you have and you are interested, I would like to hear from you. You have a total of 4 sisters and 1 brother. You are the first child my mother had. Im sorry I dont know a name she could not remember. Thanks and good luck to all of you in your searches.