。
She had one daughter with her first husband.
Literal
She [topic-は] first [genitive-の] husband [with-との] interval [in-に] 1 [counter-人] [genitive-の] daughter [object-を] begot.
もうける written in kana here is the verb 儲ける in its 'to have, beget (a child)' sense — distinct from the same verb's primary meaning 'to profit, earn,' though both flow from a sense of 'gaining.' Japanese has several verbs for childbirth, each tonally distinct: 産む (give birth, neutral biological), 出産する (childbirth, formal medical/news), and 儲ける (formal/written, with an undertone of receiving a blessing). ~との間に ('between [N1] and [N2]') is the standard frame for naming children's parentage — 'a daughter between her and her first husband.' The phrasing 最初の夫 ('first husband') quietly signals there were others — Japanese is more economical than English about implying remarriage.