The Bequest - The Birch Creek Ranch Series, #1

Two widows, six kiddos, and a will that leaves them a massive cattle ranch, but only if they work it for a year. Abigail and Amanda may have married brothers, but they have almost nothing else in common (and really, they never did get along very well). After their husbands both pass away, they have no reason to interact. Their connection drops to an awkward phone call on birthdays and an exchange of holiday cards.
Until an eccentric uncle of their husbands' leaves a massive cattle ranch to the women's minor children.