My dog is repeatedly inhaling then sneezing.?

I have a two year old dachshund and he is healthy and active. He got his shots about 1 month ago. It start happening about two weeks ago after we got the news that our 12 year old dog has lymphoma (cancer) and doesn't have much longer to live, about 5 months with steroids. At first, he would just inhale and just huff out maybe once or twice a day. But today he has been inhaling and huffing or sneezing constantly, inhale, sneeze, inhale, sneeze... He also he has a slightly running nose. He stops inhaling and sneezing for a little bit, maybe 30 mins, and starts again. I am taking my cancer dog to the vet on Wednesday for a check up on his steroids, should I bring my dachshund with to see if he is sick?