Ed Timperlake points out to me that in an underage sex investigation, all electronic communications of the investigative target are pursued. This probably led to the grand jury that was announced 11 days ago issuing a subpoena for all of the devices in the possession of Weiner and his family, including Huma. As Lucianne Goldberg quipped, they even seize the Speak & Spell toys in these cases. This grand jury is in New York, possibly less poltiically supervised than the first Hillary email investigation.
Evidently, some of these devices were not turned over in the first investigation and contained "pertinent" emails. We do not know with certainty, but some reports indicate the pertinent emails may have been found on Weiner’s laptop. Recall that the initial investigation did not convene a grand jury and did not therefore have subpoena power. It is possible that Huma Abedin misled the FBI over the existence of pertinent emails on her then-husband’s computing devices.
So what could have been on the laptop Carlos Danger used for sexting?
Con't.
You gumshoes think my sexting and wanking is bad? Here, hold these lollipops while I go into Yahoo. You want BAD, I'll show you BAD.