Is airline loyality program applicable to family members travelling together?

[subham23]

My cousin brother has an airline loyalty program (silver tier) which gives him priority check-in and boarding at international airports.
Would like to know can this be extended to his spouse and 12 years old child travelling together?

Is there any other airline loyalty program that gives member+1 or +2 to avail these benefits?
If no, is this good idea to purchase Fast Track services offered by airlines to avoid long queue at ticket counter and boarding for international trip?

 

[da3m0n]

If everyone is booked in the same PNR then I guess the same benefit is extended to everyone. Not sure on the boarding part but check-ins can be done together.

 

[subham23]

If everyone is booked in the same PNR then I guess the same benefit is extended to everyone. Not sure on the boarding part but check-ins can be done together.

Thanks, hope check-in and luggage drop will work on priority as now-a-days they just allow primary person in queue while remaining members are waiting side-by.