Third Strand of the Cord by Catherine Richmond

She prayed for a fairy godmother and got a… karate instructor? Hard-working single mom Caroline Jameson wonders why her son is so unruly. Weren’t children with Down syndrome supposed to be cuddly and compliant? Her ex says the boy belongs in an institution. Caroline will do anything to prove him wrong, even sign her son up for karate classes with a know-it-all instructor. Lee Marivaux is an expert at reading people. He knows his feisty new student will thrive with firm guidance - and he’s right. He pegs the boy’s mother as a clueless socialite who loafs at the country club - and he’s never been so wrong. It’s a battle of wills and misperceptions - until Caroline’s abusive ex shows up, demanding custody. Can Lee and Caroline join forces to keep the boy safe? And in a town called Liberty, will love give them the freedom to braid themselves into a strong new family?