River, the real-world dog that inspired Fallout 4’s Dogmeat, has died. River’s owner, Joel Burgess, confirmed the news in a heartfelt goodbye posted on social media.

“I said goodbye today to River, who most of you know as Fallout 4’s Dogmeat,” Burgess said. “Heartbroken doesn’t cover it, but I won’t eulogize her here. For twitter, I thought it’d be appropriate to look back at her impact on that game.”

Across a series of tweets, Burgess revealed a series of fascinating deals and insider information about how Bethesda went about putting River into Fallout 4 as DogmeatCome from Sports betting site. Burgess also spoke about how the studio wanted to avoid making Dogmeat feel like a “canine weapon and nothing more.”

“What we wanted was a companion first, and a combat ally second,” Burgess said.

The team considered casting a “professional” dog who had formal training for media or with the police, but Bethesda decided to cast a developer’s own dog (Burgess has since left Bethesda to join Capybara Games) because it was the right fit for the project. The choice was well receive and Dogmeat even won an award.

You can see a selection of Burgess’ tweets about River below, while the rest are available on Twitter. You can also remember River by watching the video below that shows how Bethesda went about bringing River into the game. And finally, Burgess encouraged people to volunteer with animal rescue campaigns where they live or make a donation.

“Dogmeat is a tether. He grounds you in the world, will always stand by you, lead you to your family, and anticipate your needs. He wants you to be safe and happy.nIn other words, he loves you. And if love is River’s legacy, I am contented,” Burgess said. “Rest in peace, big girl.”