Deepa Lakshmin, writing for MTV:
Interestingly, Blink-182 have their science wrong. Though extremely rare, it is possible to get a girl “more pregnant” if she continues ovulating after already getting pregnant. This phenomenon is called superfetation, and doctors have no clear medical explanation for it yet.
BBC reports that there have only been 10 recorded cases, but the babies are typically born healthy as if they were twins — even though they were technically conceived days or weeks apart. Man, human bodies are weird.