Spot the difference

An unbelievably abyssmal day weather-wise so son number 1 has been giving me lessons in Photoshop. He was messing around with his dad's winter hat when it struck me that he looked exactly like his great grandfather - a quick photoshoot (he's very bossy) and a revision of yesterday's photoshop lesson and  a lot of laughs later and we have a result.
The photo of Great Grandpa Joe was taken when he had just returned from an expedition to the North Pole in 1924. He was the engineer and pilot on the expedition which, along with ponies and dogs, also incuded a bi-plane. More about him can be read here .
Son number 1's beard is the result of him not being arsed to shave, and  a fine thing it is too! It attracts a lot of attention - mad Anglo-Saxon or what!