On the 1901 and 1911 Irish Census my great great grandparents had a lodger staying with them. The family name was Fieldman and they lived in Londonderry at the time. On the 1901 Census a Harry Kaufman, age 28, born in Austria was living with the family. The census stated he was an Upholsterer by trade and was married. He was recorded as a "Boarder". On the 1911 Census a David Seligson, a single man, age 27, born in Russia (Vilnius), an unemployed Metal Turner who was a "Visitor" was staying with the family. The Fieldman family was recorded as being from Russia also but I now know this is from what is now Ukraine. The Fieldman family originally lived in Dublin before moving to Londonderry and then on to Belfast.
There are no other Irish records for either of the two visitors but I did find David Seligson having arrived by boat from the United States on the day of the census. He had been living with a brother Joseph Seligson in Minnesota. 
How would these visitors known who to contact? There wasn't a huge Jewish population in the area. Could they have been relations? How would I go about proving this? I don't know any relations at that level of the family other than the immediate family recorded on those census records. A Jewish register for Londonderry in 1901 had a total of 60 names including children. In 1911 it was only 32 including our visitors. They must have known who they were going to be staying with particularly David Seligson as there were only 6 families in the city at the time.
I seem to be scraping around looking for any hints I can about family relations.
Thanks for taking the time to read this.
John Edwards

Boarders and lodgers in the England and Wales Census, and likely Northern Irish Census, were often relations, siblings, cousins, nephews and nieces etc. In the 1891 Welsh Census, my grandfather Samuel Servian was staying with his elder married sister Leah Goldblat in Mold in North Wales. He was given as a boarder rather than brother. I have other examples in the family too, also from 1891, when Samuel's cousin Lazarus Karpowitz  was staying with Samuel's father and mother Joseph and Ada in Liverpool. Ada's maiden name was Karpowitz and Lazarus was her nephew.  Lazarus was acting as an apprentice to Joseph, but when Leah died of typhoid a few years later, Lazarus left for New York, and Joseph and Leah became stand- in parents for Leah's three young children. 

So do not dismiss boarders and lodgers, as often they were relations.

Jill Whitehead, Surrey, UK

John,

There is David Seligson's 1908 passenger manifest when he entered NY, bound for his brother in Minnesota, and he left behind his mother Sarah Seligson in Vilna.

Perhaps some of this info will be helpful in your search.

Sherri Bobish

Thank you for that Jill. I will be exploring the families of both Harry Kaufman and David Seligson as best I can. 
The thing with this type of research is don't give up. One day I will confirm details one way or another.
If nothing else I will learn of the social history of the time and hopefully understand better the type of lives that my ancestors led.
John Edwards

My great grandfather, a tailor, had boarders in both London and New York. In London, one was his younger brother, but the other five I'm pretty sure were employees. They were all tailors, and my ggf, like many others in his line of work, ran a shop in his home as part of London's garment industry. He did the same in NY.
Sherry Robinson