There is no Ico 2, nor will there ever be. Oscar Römer's take on what he'd look like all grown up, though, kinda makes me wish there was. Even if it took *checks Last Guardian development calendar* 117 years to make the thing. Römer is a freelance artist based in Germany, who has worked for companies like DeNA and Fantasy Flight.
You can see more of Oscar's work at his ArtStation page.
Fine Art is a celebration of the work of video game artists, showcasing the best of both their professional and personal portfolios.