No didn’t have a dog .

I am not sure there is a consistent difference between American and British English on this point. Generally, questions are said with a rise in tone toward the end, but there can still be a question even if the statement doesn't rise in tone. Statements starting with "why", "who", "what" and so on are obviously questions. But a statement like "The dog is sitting" can be made into a question with a rising tone. The rising tone is what indicates this is a question. "The dog is sitting?" Assuming you want to be understood, usually a good objective in communication, it is best to always use a rising tone for questions. Sometimes listeners aren't sure and they have to ask "Is that a question?". I hope that is helpful.