Banished in the Deep Mountains, I Get Three Daughters from the Start

[Historical farming + raising children + pocket dimension + building wealth + marriage first, love later + unconventional plot + devoted couple] She transmigrates into a remote mountain village. News arrives that her husband has died on the border, and her parents-in-law meet with disaster soon after, leaving his family in ruins. She is still just a child herself, yet now she has to be a daughter-in-law...

And three little girls are crying to be fed.

The road ahead is bleak...

One of the Seven Grounds for Divorce is having no children. As her mother-in-law lies dying, she uses this as a reason to send her daughter-in-law away. As she sees it, the young woman can marry again and start over. She doesn't realize that in this world, only a husband has the right to divorce his wife... Not even parents-in-law or clan relatives have the authority to do so.

There is no way to separate by mutual consent, no way to divorce her, and no one else can even write a letter of release on her husband's behalf.

"Sister-in-law, boo-hoo... Wherever you go, we'll go too... If you drink porridge, we'll have broth. We'll even eat bran and vegetables..."

Wait, what? That guy... A military officer, and he wants to sit the imperial examinations to become the top scholar?

How about we go home and have children and raise them instead?

Her three younger sisters-in-law plant their hands on their hips and point at their brother. "Listen to Sister-in-law and you'll get meat to eat! Be good, come on, let's go home!"