"Big Brother" producers broke the news to Ariana Grande's brother late Wednesday that his grandfather passed away -- and the whole 'BB' house is rallying around him.
TMZ broke the story earlier today ... Frankie Grande's grandpa died on Tuesday, but Ariana obeyed his final wish -- to let Frankie continue on 'BB" despite his illness.
But this evening producers passed a note to Frankie from his family ... which revealed the sad news.
According to bloggers watching the 'BB' live feed -- Frankie broke down in tears and shared the news with everyone else in the house. Some of the other house guests are crying too.
Frankie's grandfathers death has hit Zach. Zach is crying in the lounge alone. Zach: "This sucks!" #BB16
— BigBrotherLeak (@BigBrotherLeak) July 24, 2014
Still unclear at this point who made the final call in this case. We've reached out to producers ... but, so far no word back.