When your dog locks eyes with you, it may genuinely be a look of love, and not simply a form of begging. Dogs can develop this atypical behavior with close human companions — while between dogs or with a strange person, a direct stare is a threat. Of course not every glance from Fido is loving — he may simply want your dinner. Or, if his body is tense and ears flattened, he may be telling you to back off. Dogs can sniff out a dangerous drop in blood sugar in a diabetic owner and alert the person to take action by pawing, licking, whining, or barking. A few dogs have even been trained and placed as diabetic service dogs. Their nose for hypoglycemia (low blood sugar) is correct 90% of the time, according to their trainers. Source: webmd