The 1881 family is living at 8 West Bank St., Widnes, Lancs-
Peter Blong 24 Ireland [born c1857]
wife Mary Blong 26 Ireland [born c1855]
son Edward Blong 2 Widnes [born c1879]
son Peter Blong 1 month Widnes [born c1881]
It certainly looks like this could be Peter Blong and wife Mary Murphy- and if that's the case I would search for the marriage in England first.
And, sure enough, they married in England-
Peter Blong/Mary Murphy, Sept.1880 quarter, Prescot registration district 8b 1063 (see free BMD).
The marriage certificate should list their fathers' names.