David Goldberg, one of Silicon Valley’s most high-profile, well-regarded and well-liked entrepreneurs, died suddenly last night of undetermined causes.

News of his untimely death was posted on Facebook by his brother and also confirmed by people close to his family. Goldberg, 47, was the husband of Facebook COO Sheryl Sandberg — they have two young children — and the CEO of SurveyMonkey. He also previously worked at Yahoo, after it bought his online music company many years ago, and was an active angel investor.

A much-admired and beloved figure in the tech and media scene, he was also my friend and the news of his loss is simply devastating. His unfailing kindness toward everyone, endless generosity with his time, insights and advice and basic great-guy personality made Dave — no one called him David, really — the heart and also soul of the tech and media community. (He also loved poker and it loved him.)

In a Facebook post, Robert Goldberg wrote:

It’s with incredible shock and sadness that I’m letting our friends and family know that my amazing brother, Dave Goldberg, beloved husband of Sheryl Sandberg, father of two wonderful children, and son of Paula Goldberg, passed away suddenly last night. In this time of sorrow, we mourn his passing and remember what an amazing husband, father, brother, son and friend he was. No words can express the depth of loss we feel, but we want his children to learn how much he meant to all of you. In lieu of donations, we want to celebrate his life in a manner that respects the family’s privacy as they cope with this tragic, life changing event: Sheryl, their children, and our family would be grateful if people would post their memories and pictures of Dave to his Facebook profile.

The post was soon filled with memories of Dave and condolences to Sandberg and her children. You can add to that here.

More to come, but what a tragic moment. Dave was a rock for so many that it’s incomprehensible he is gone.

But never, ever forgotten. Here are the lovely photos that were posted of him and also of Sandberg on Facebook.