The Baby Plan (Tess and Tilly Mystery #11)

In book 11 in the series, Tess fills in at the post office after the woman who took over her route broke her leg. While on route for the first time in a year she discovers that her father has left her brother Mike with a baby to hide and protect. Tess has never really been one to go all gooey over babies but when she discovers this particular little darling in need she enlists Tony's help to make sure she is well hidden and to look for the babies mother.

Meanwhile Tess's mother has a new boyfriend her father isn't too happy about and Mike has a new murder to solve.