Amazon SDE-intern interview questions

There is one man (named GG for great grandfather) who is throwing a party in which his entire family is coming. Every person in the party has to tell his straight path connection to GG at the reception. You need to write a code to inform that person about his junction point (if there is any) in the path till GG. That is, you need to tell him if he has any uncle or relative (cross branching).