The Cinderella Debutante by Elizabeth Hanbury

I wanted something light and romantic and this fitted the bill. I've read all of Georgette Heyer and this comes close, not GH but close.

Frivolous, extremely pretty Belinda with the scheming mother come to London to ensnare a husband for the pretty Belinda. The elder sister Lucy (who is a step sister) is almost on the shelf at 23, her earlier debut cut short by the death of her father and return to the country. Mother and younger daughter have forgotton about Lucy and cannot even imagine her attracting the attention of any eligible bachelor around.

Lucy's godmother and grandmother have not forgotton about her and are determined that during this short stay they do something and introduce her to someone who may be the correct partner for Lucy. On her own, Lucy does quite well without any help from anyone but unfortunately the person whom she is attracted to is also the man whom Lucy's step ma is marking out for her pretty Belinda. There is also a villain in the form of a dissolute penniless Lord in the background also vying for Belinda's favours.

As in all Regency romances there are skirmishes (no duels), almost elopements and rescues and everything ends very happily.

Just what I needed on a tiring afternoon!