I have yet to see anything to justify the assertion that she was born in (a) Luton in (b) 1724.
There's a public tree on Ancestry that suggest she was born c.1724 in Luton but it has no more details for her... However it does suggest Francis How was baptised Luton on 16 May 1722 son of Francis & Jane How, and that Francis senior married Jane Mallard at Luton on 2 Mar 1714. Both these facts are confirmed by the Luton PR transcript.
But there was another Francis baptised 24 Dec 1714, son of Thomas & Susannah How.
Also there is another Francis How marrying in Luton on 20 Sept 1754 to Mary Ebbs
Baptisms of children to Francis & Mary How in Luton
19/05/1741 Susannah
22/05/1743 Mary
10/03/1744 John
15/03/1746 Sarah
23/04/1749 Judith
08/09/1751 Elizabeth
&
08/02/1756 Francis buried 21/02/1756
I'd hazard a guess that the first 6 are from Francis & Mary Cooper & the last one from Mary Ebbs.
Also for information to anyone interested...
Jane How wife of Francis buried 27/02/1747
Susannah How, widow buried 24/01/1759
Francis How buried 25/09/1761
Mary How wife of Francis of workhouse/pesthouse buried 09/05/1777
Mary How wife of Francis buried 27/09/1780
Francis How 'the bellman' buried 24/02/1782
Francis How of the workhouse buried 10/02/1783
As to which of these is your Francis & Mary
I will leave to you !
Cheers John