Katie Winters had the kind of laugh that filled a room—warm, genuine, without pretense. Emma found herself smiling in response as Katie described her five-year-old's recent dinosaur obsession.

"He corrects the museum guides," Katie said, eyes crinkling with amusement. "They're very patient with him."

They sat in a quiet corner of a café near Massachusetts General, where Katie worked as a pediatric nurse. For their first meeting, Emma had suggested somewhere casual rather than the sterile agency offices.

"Your children are adorable," Emma said, admiring photos on Katie's phone—a boy with a gap-toothed grin and a slightly older girl with serious eyes and wild curls.

"They're my everything," Katie said...