Hi and a warm welcome
I see from the 1891 (RG12 1854 114 22) that Philippa is in St Ives Cornwall, age 28, 2 children age 2 and 9 mths, and numerous Chard siblings.
There are several births on FreeBMD of Benedict Quicks, in Cornwall (though of course he may have been born elsewhere) so without some more info about him we wont know which is him.
Have you got the marriage cert?
That would be a good place to begin. It should give a father for Benedict, an occupation, an address maybe, and hopefully even an age, so might help pinpoint him in a previous census before his marriage and untimely death.
(Out of interest have you seen 1901 - Phillipa has remarrried to a Mr Farrell RG13 2249 95 10)