He might not remember his first few Christmases, but you can always take lots of photos! And children his age seem to like interactive toys. I've got baby cousins who love anything with varying textures that they can play with, like toys with shapes to put into appropriate holes, stacking cups and blocks, light up and noise making and singing toys, and riding toys to scoot around on. One even has a portable ball pit to play in. And they seem to also enjoy fun bath toys and books with big, bright pictures.
I don't mean to overstep, of course! Just trying to help.