Any two can play (1981)

https://www.fictiondb.com/author/elizabeth-cadell~any-two-can-play~3679~b.htmAttractive, twenty-seven-year-old Natalie Travers has taken it upon herself to rescue her brother from domestic chaos. His wife has left him with twins to care for, and egotistical Julian just isn't the paternal type. Natalie takes over, determined to find the proper nanny. Independent and happily unmarried, Natalie feels no pressure to change her status -- her brother's situation is hardly an advertisement for the joys of marriage. But when romance appears quite unexpectedly in the form of Henry Downing, Natalie is convinced that they will make the perfect couple.