Céline Dion might find getting right back to work therapeutic while mourning the loss of her husband René Angélil.

The singer is currently scheduled to take the stage at Caesars Palace in Las Vegas on Saturday, one day after Angélil's funeral at Notre-Dame Basilica in Montreal – where the couple wed 21 years earlier.

"That's what René would want. He wants her to perform and come back," a source tells PEOPLE. "He knew her better than anybody and he probably knows that's what she needs too, to perform."

Angélil died on Thursday at the age of 73 and Dion, 47, is said to be "extremely heartbroken," according to a source. Adding to the heartbreak, the singer lost her brother Daniel two days after Angélil.

In the last year, Dion rarely left her husband's side. Angélil relied on a feeding tube, and had both "good and bad days," says the source. "Some days he could get up and walk around the room, play with the kids. Some days he was too tired."

"She didn't travel anywhere," adds the source. "She wanted to be with him 24/7 in case anything happened." And she was with him – Dion was at home with their three children when Angélil died.

The singer and her late husband's business associates in Vegas are also feeling his loss.

"We are heartbroken to hear this news," AEG Live Las Vegas Vice President John Nelson said in a statement. "Not only because René was a great friend and mentor and an extraordinary partner with us in these shows at Caesars Palace for the last 13 years, but even more because he and Celine were so devoted to each other; their relationship has been a model for us all.

"René was the most brilliant, generous and loyal partner one could have in business," said Nelson. "And after the work was done, René was such a fun and joyful friend who loved to entertain, eat amazing meals, and tell great stories. There will never be another one like René."

For much more on Dion and Angélil's love story and how the singer is focusing on the couple's children, pick up the latest issue of PEOPLE, on newsstands Friday.

Gary Selesner, President of Caesars Palace echoed those sentiments.

"We are incredibly saddened by the loss of our friend and partner René Angélil," he said in a statement. "Our heart goes out to Céline and the family. It is impossible to overstate the impact René and of course Céline have had on the history of entertainment in Las Vegas and at Caesars Palace, with his audacious vision regarding her residency, now 13 years and counting."

"René was truly an amazing human being, showman and businessman, and over these many years became a loved and cherished member of the Caesars Palace family," he added. "On behalf of our owners, management and employees, we will forever be grateful for his love and friendship. On a personal note I will miss him greatly. There will never be another René Angélil."