Obtaining the Steam ID of someone who has invited me to a group

[Robert Lutece]

Hello. Thank you for reading my post.

I have been scratching my head for a while, trying to figure out a method to find the Steam ID of someone who invites a user to a group.

 client.on("groupRelationship", (sid, relationship) => {
   if (relationship === 2) {
     client.respondToGroupInvite(sid, false);
     console.log("Group invite declined.");
   }
 });
}

Currently, the only way I have managed to do it is by manually searching through the friends list to identify the friend who is in the group, as only friends can send group invites. However, this approach is certainly far from ideal. I would greatly appreciate any suggestions or ideas. Thank you kindly and have a nice day.