Downton Abby AU Plot Bunny

[beatrice_otter]

What if Mary got pregnant when she slept with Mr. Pamouk in the first season? To hide things, she and Cora (and probably O'Brien, too, because ladies didn't travel without their maid) go to America "to visit" (but really to have the baby in secret), and they come back telling everyone (possibly even Robert) that the baby is Cora's. (This sometimes actually happened, in the past--an unmarried daughter would get pregnant out of wedlock, and the family would pass it off as a late-life baby of the mother's, to avoid scandal.) If the baby is a boy (and the birth certificate says it's the son of the Earl and Countess of Grantham), it becomes the new heir--not cousin Matthew. (This would be strong motivation for Cora to tell Robert the baby is his, if it's a boy. Robert would probably be too honor-bound to consider the deception, if it would mean disinheriting someone else. Cora already thinks the whole heir business is silly, and would probably prefer the title and money and all went to a bastard grandson than to some random cousin several times removed.)