active directory - Load AD group members to include nested groups c# -

i using ad populate list of company associates.
have ad group iterating through (using system.directoryservices.accountmanagement) populate list. group in question contains nested groups (following recent company merger) seems nested group members aren't being included.

// members of specified ad group...         groupprincipal group = adm.getgroup(adgroupname);                      // iterate on members         foreach (principal p in group.members)         {                 // data user...             var groupmember = adm.getuser(p.samaccountname); 

from here determine if user enabled , not expired , if both true, add name sorted list (which cache 24 hours) due it's size.
there need nested groups included, or have append second group end?

ok, bit more googling , found this...

foreach (principal p in @group.getmembers(true)) 

so instead of getting members, recursively members!