You know this really irritates me. I feel like this is a slap in the face to people who watched the first movie and grew to like Charlie and Rinko. What, after all that he just up and leaves and doesn't come back? Also, Idris Elba having a son really kind of casts shadow into his character being a bit of scumbag. In the first movie he raised Rinko like she was his only child, and yet he has a son that is mysteriously out of the picture nobody bothered to mention?
This is like if after the first Star Wars movie Luke is suddenly absent in Empire Strikes Back, and Leia hooks up with Han Solo's mysterious son never mentioned.