Алексе́й Никола́евич (12 Aug 1904-17 July 1918)
Tsarevich Alexis in 1913 when he would have been about 9. The youngest of the family he was affectionately called 'baby'. Famously he suffered from haemophilia and his parents appointed 2 sailors from the Imperial Navy to look after him so he would not hurt himself, maybe that is why he is wearing a sailor suit. His parents had prohibited from riding a bike, I guess they were not too successful, although perhaps they weakened thinking three wheels were more safe than two.
When Nedis sent this card at the end of January in was minus, that is -30°, not the weather for riding bicycles.