After a little confused googling, I assume you mean the
Bure Valley Railway, and tickets to
Aylsham rather than Aylesham which is a NR station in Kent.
It is possible to get a
combined NR+BVR fare, at £9 adult, £6 child over the rail fare (for a 'Rover' giving unlimited travel on the BVR). This is cheaper than the fare on the railway itself. Railcard discounts apply, but only to the mainline leg.
It sounds like it may only be available from NXEA stations; I can't bring it up as a destination on National Rail.