Sure sounds like you were related or from the same spiritual family.... one exercise i thought was great, that i did in a psychic development class i went to was--

the class was divided into a 'test subject' and the rest of the class. the test subject had a question that she wanted answers about - but she didn't tell the rest of the class what it was.... we were all directed to dream about her problem - and to get up and write any dreams down, no matter what time we awoke. before we went to bed, we were to remind ourselves to dream the answer to the question. the next day, we all told the person our dreams -- and they had many similarities. after we shared the dreams, the woman we had dreamed for told us her problem - and we were astounded. the answers were very appropos.

so i think that if you two decide to dream the answer, and write down the dream, and then talk about it, you might get somewhere.

of course, the other easy option is to go to a psychic/past life regressionist and get the answer. :)

You can tell by the eyes if they are related of the past back about 170 years, after that it would be harder to tell. The human body subconscious can pick it up seeing more than we can consciously see in the eyes of others seeing the patterns of lines of the eyes. With training it is possible to pick it out.
If you have a lost relative, or wonder if someone is really your father or mother this would work. You could ask your inner self to nod yes or no if related. The naturalness of the nodding will support the answer.

Being related in another lifetime is possible having interbred with someone of the past of the same genetic strands of the live person. Two people interbreeding which are relatives of the past of the same genetic information. Like both of you having the same ancient relative mother 10,000 years ago in Egypt speaking in both of you on the genetic strands.