Quote Originally Posted by Meadow910 View Post
We adopted a female ball python about 3 years ago.... The new male is a bit smaller.

While I wouldn't house two snakes of the same sex together for reasons stated by others above, you should not house two snakes of opposite sex together. Odds are you will end up with eggs, and while there's nothing inherently wrong with that, it sounds like they're both normals, and you could very suddenly find yourself with 6 or 8 or more normal ball pythons to house. Normals are beautiful and have merits of their own, but unfortunately they are notoriously difficult to find good homes for.

Even if you didn't incubate the eggs, the breeding process is exceptionally taxing on the female's body, and you might find her (and even his) condition deteriorating rather quickly if they continually copulate. A 3 year old female is almost certainly mature enough to breed, even if she's not "big enough" by a breeder's standards, just like a 13-14 year old human girl is capable of becoming pregnant despite all recommendations against it. The male may be smaller, but they become sexually mature much faster than the females, and no matter how many grams he weighs now you can't be certain that he isn't capable of it.