Ok thanks. Can I give the passes to my wife to use it? And a 5 year old child?
No, it doesn't work like that. You have to present your Priority Pass membership card, your boarding pass, and some ID. You can guest someone in for US $27, which will be charged to your Citibank card.
I used both of my freebies during the previous membership year. On the first one, I was travelling alone. On the second, Mrs 2905 was with me, but PP had a promo on where you could guest someone in to a particular lounge at LHR at no charge. Just as well; it wouldn't have been worth paying for, IMO.
There was a loophole where additional Citibank cardholders could sign up for their own PP membership, but that seems to have been closed. (The T&C's always did state that it was only for the primary cardholder, so we can't complain.)