Elizabeth jr. is perhaps a grandchild. Often illegitimate children appear in a census as a child when they are grandchildren.
What is the source of your info (dates, name of spouse, etc.)?

Brian Lawsons birth index shows an Elizabeth Cowin born to Isabella Cowin (no father's name) in Ramsey on August 25 1888. At the time of the 1891 census she is living with Thomas (67) and Elizabeth (53) Cowin. Elizabeth Kinnish (83 mother-in-law) is also
Isabella 12 in 1881)is the daughter of Thomas Cowin (57 in 1881) and Elizabeth (43 in 1881).

Also if this is the family, Frances may be on target with her reference to Query. Spellings include Kinnish, Kennish Kenneth & Kerrnish.
Bruce