I've just got a cheap copy of Albert's birth cert - Q1 1852 Warwick, which I referenced earlier
Interestingly. it reads
born 14th December 1851, Althorp (?) Street. Leamington
Name Alfred Boy
Father William Day (railway labourer)
Mother Mary Day formerly Plant
Informant Mary Day, formerly Plant 15 Jan 1852
Gadget
Check 1851 for a Mary