Is rebirth a true phenomenon? If yes can we find out where a person has re birthed?
The evidence for reincarnation is persuasive, though like so many after death experiences, difficult to prove in a scientific way.
Nonetheless, it has been taught since time immemorial and no less than Krishna in the BHAGAVAD GITA affirms its truth.
But, you ask: “How can one find the rebirth of a loved one?”
This cannot be achieved by just anyone. The power to pierce the veil past death and to know the flow of karma in the evolution of a soul requires the wisdom of saint: a highly advanced saint.
Paramhansa Yogananda describes in his famous life story, Autobiography of a Yogi, how he found the boy Kashi re-born in Calcutta after making a promise to do so. It is an interesting chapter to read.
Yogananda demonstrated this power at least one other time that I have heard of.
Yogananda referred to a technique by which this could be done but few living today know the technique and few living today would have the karma and spiritual subtlety and purity to use the technique successfully.
Be reassured, however, that true friends will reappear in our lives from lifetime to lifetime according to the karma we share.
Rest assured, also, that our sincere prayers and love sent to a now departed loved one will find their target if our intention is sincere and pure (and not to affirm our attachment or grief).
I hope in some way these words will find comfort and truth in your heart.
Blessings to you,