The best strategy when being the bearer of bad news?

I’m pet sitting for my mom, her 14 year old doberman rescue that I gave her 13½ years ago. While I had her, I figured I’d give her a senior wellness check and a set of radiographs because I’ve noticed a mild cough while she’s been here.

I found a nodule in her lung, and it’s highly likely to be cancer. She’ll be getting an ultrasound tomorrow to see if it’s primary or secondary (metastatic) and when her bloodwork results come back I may or may not get a ultrasound guided biopsy to confirm (depending on her blood values and her met check).

Mom loves this dog, probably more than she loves my dad. But she’s not likely to pursue chemotherapy (and I wouldn’t either, if she were mine). I’m not going to tell mom while she’s on vacation, but I will when she picks up her dog.

Any suggestions?