When I was young, my sister and I were offered 2 Guinea pigs. Both were females.

After some time, my sister's one started to become bigger and bigger. We thought it had something wrong, probably a desease or something. We did not know how to handle it.

Should we stop feeding it or give it a special cure ? After some days, it started to move inside its belly .

My mother understood that the animal was pregnant. Finally it made 2 beautiful babies.

It was amazing to get babies though we only had females.

After thinking of it, we realized that my sister had taken its Guinea pig with her to school and it had met a male there brought by another schoolgirl.