i work at a petstore and ive owner 10 guinea pigs and i have 3 right now, and id recomend, getting another female for sure, or youll be having new babies in just a couple months. introduce them SLOWLY, because guinea pigs will fight unknown piggies. you should put them in seperate cages next to eachother forlike a week, and then if that goes well and theres not too many threatening sounds, let them loose in a small room thats closed with nowhere they can hide, and watch them. try this alottttt. and then put them in a big cage together and watch them, if its 2 females it probubly will work, but dont put 2 males together who didnt grow up together because they will fight. i hope it works!