This four-year-old and his puppy came up with the best training programme

Four-year-old Lincoln Ball is allergic to pretty much "everything outside," and, in particular, has a severe reaction to pollen which means he has to stay indoors during allergy season.

But there was one bright side, as Lincoln’s dad Daniel told ABC News.

"The allergy doctor said half-jokingly, ’Well there’s good news and bad news. The bad news is you’re allergic to everything outside. The good news is you’re not allergic to pets. You could get a puppy’."