Yes . It can be done. Whenever a new person joins the organization ,asked to fill PF Nomination Form 2 .
wherein it's clearly mentioned to fill under EPS , to nominate any person apart from family member .
Can nominate brother's name / his son or daughter / sister's name / her son & daughter . or can mention as clarified by Prachanda.
Also attaching PF Nomination form 2 for your reference .