How certain are you about this information ? as I have different relationships between these people.
For example, I have John Killip who married Margaret Looney as being christened in 1799 to William Killip and Jane Kewley, all from Lonan. William Killip and Elizabeth Taggart appear to have raised a family in Ballaugh.
According to my records John and Margaret's daughter Margaret (b. 1851) married James William Gardner - is this the same Margaret who married John Robert Cowell?
If you can ease the confusion, I can probably help you with your family tree. If you are descended from the same John Killip, then we are possibly related through a common ancestor William Killip, born in 1570 in Ballaugh - I am John's 11th cousin, six times removed, although some of the ancestral links are conjectured pending evidence (if it can ever be found!).