Hi there
Thank you all for your input. Brian is correct in that John cannot be Robert's son if the dates are correct. Also Ann's dates are strange.
The IGI record for Ann gives her as christened 22 Aug 1781, Douglas and has her marrying James Gawne in Douglas 19 May 1812.

There were 3 children: Ann Susan Gawne abt 1816 ( married Robert Quiggin in 1846); James Gawne abt 1816 and Eleanor Gawne chr 8 May 1818.
Eleanor married the chemist William Arthur Brearey.

In 1851 there is an Ann Gawne b. 1791, lodging house keeper, with niece Mary Ann Quiggin b. 1817.
In 1861, Mary Ann Quiggin, b. 1815 is with her cousin Eleanor Brearey als Gawne and family.
This Mary Ann could be the daughter of John Quiggin and Elizabeth Christian as mentioned in the M.I.("Also Mary Ann
Quiggin who died on the 21st April 1874 aged 65 yrs" = Mary Ann, chr 9 Sep 1811, and makes John the brother of Robert which makes more sense).

Have I got this all totally confused and was there another Ann Quiggin-Gawne marriage?

Thanks for any ideas

Jane