When can i sell my baby boy guinea pig?

im uming you live in australia because the way your spelling "mum" so you can try a website called gumtree.com.au and you can put a add up for free and try to sell your guinea pig that way. or you can call petshops and ask if they want a guinea pig, i got my guinea pig when he was 4weeks old from a petshop i don't know if they do try to breed with their mum and siblings but apparently so. so yes you can sell your guinea pig at 4weeks old.