Did John Lennon have any brothers or sisters
http://en.wikipedia.org/wiki/John_Lennon#Early_years:_1940-1957
=)
To find out if John Lennon had any brothers or sisters, you can refer to the Wikipedia page dedicated to him. Specifically, his early life section from 1940 to 1957. Here is the link to the page:
http://en.wikipedia.org/wiki/John_Lennon#Early_years:_1940-1957
By reading this section, you will be able to gather information about John Lennon's family, including whether he had any siblings.