Well, these days, series is now more than just a television series. I think they're going to do a film series.
Secondly, Sophie(sorry for the mistake) is that girl who befriends the giant, because that's her name.
...The link
very specifically states that they're following up the film with a TV series, rather than doing a sequel as a film. Also,
Big Hero 6 doesn't have a character named Sophie, nor does it involve anyone befriending a giant, so I have absolutely NO idea what you're on about.
Maybe go read the link that I posted since you seem to be talking about something entirely unrelated.