Catherine Mooney was buried in the same grave as her son Matthew. He died in 1924.
Just beat me to it heywood :-)
His death notice is in the Liverpool Echo
Liverpool Echo 8 Oct 1924 page 6 col 6
MOONEY October 4, suddenly, in his 37th year, MATTHEW (Matt), the dearly loved husband of Lydia Mooney 49 Boswell Street. Interment at Allerton Cemetery tomorrow (Thursday) at 2 pmso that burial for Catherine is starting to look very likely now as her entry in the Allerton register did say it was a 'subsequent' burial (i.e. not the first burial in that grave).
As an aside it sounds like Catherine had been ill for a while (?possibly a stroke in 1919)
1919
Sefton General Hospital (Toxteth Park Workhouse) Admission, DIscharge and Creed Registers
admitted 25 Aug 1919, discharged 10 Sep 1919
"Kathleen" Mooney, d.o.b. 19 Aug 1865
reason for admission Hemiplegia
address 7 Noel St
religion R.C.
information given by son
married to James , a plasterer
Boo