Daddy disappointed we're having a girl?:(

My SO really had his heart set on us having a boy...he's a keen sailor and fisherman and feels as though he won't be able to pass his interests on to a daughter. He's also worried he won't be able to relate (obviously because he's never been a girl before, and he'll be outnumbered by baby and I) - how do I make him feel better? Will this change once he meets his daughter? Any advice welcome xo