My, haven't you grown? Massively multiplayer, creative construction game Roblox is celebrating its 13th birthday with a video, in-game anniversary items, and a handful of social media giveaways ...

So Robby had a virtual birthday party in Roblox instead. The invitees logged into Google Hangouts first, where they chatted and sang “Happy Birthday.” Then all the kids jumped into Roblox for ...