The German Shepherd passed at the White House Saturday ... and Jill says he went peacefully.
The First Lady tweeted, "'RIP to our sweet, good boy, Champ. We will miss you always."
Champ moved to the White House with the Bidens and their other dog, Major, in January when the president took office.
The President and First Lady issued a statement ... "Our hearts are heavy today as we let you all know that our beloved German Shepard, Champ, passed away peacefully at home. He was our constant, cherished companion during the last 13 years and was adored by the entire Biden family. Even as Champ's strength waned in his last months, when we came into a room, he would immediately pull himself up, his tail always wagging, and nuzzle us for an ear scratch or a belly rub."
They went on ... "Wherever we were, he wanted to be, and everything was instantly better when he was next to us. He loved nothing more than curling up at our feet in front of a fire at the end of the day, joining us as a comforting presence in meetings, or sunning himself in the White House garden. In his younger days, he was happiest chasing golf balls on the front lawn of the Naval Observatory or racing to catch our grandchildren as they ran around our backyard in Delaware."
They ended with this ... "In our most joyful moments and in our most grief-stricken days, he was there with us, sensitive to our every unspoken feeling and emotion. We love our sweet, good boy and will miss him always."
Champ was born in Pennsylvania and the Biden's got him as a puppy. His granddaughters named him.
Champ was 13.