As the dog days of summer approach, don't be afraid to let your dog enjoy the water. But be aware if they're drinking a bit too much of it. An 18-month-old dog was filmed cooling off in a pool. However, the pup gulped the water. Suddenly, the dog's owner noticed something strange, which led to the dog dying of water intoxication. Veterinarian Dr.Timnah Lee emphasizes that water intoxication in dogs is rare but real. However, Dr. Lee says you should know the warning signs.