Gave my brother my 1st PCP.

Yes, gave my 57 yr old brother my 1st PCP, Hatsan flash. 

Not here to bash Hatsan, it was an entry level gun and propelled me into the progression of finer equipment. 

As I invested into top tier guns, the Flash became a blast in the past and simply sat collecting dust.

It will suffice for his purpose as varmint control but met it's demise once I joined this forum and discovered holy grail in uncanny accuracy in PCP.

My current stable will out perform my center fire within reasonable distance. 
 
Good for you & good for your brother. Now you have a fantastic shooting partner when schedules allow & he has a source of filling his gun. If you have a compressor, buy an inexpensive SCBA tank on eBay. (be very selective) A 30 minute small tank can be pretty cheap. Get him a proper fitting adapter so he can fill his gun. Those would be a really great birthday or Christmas present. Then at some point down the road, you'll be able to welcome him down the rabbit hole as he wants a faster & better gun like you have.