ABANDONED. Historic Romance with a young girl pretending to be a teenager

[Kelsey]

The book opens in America and a young woman is asked to help get a younger girl to England to escape the war. She takes her pregnant sister and crazy grandmother with her. The young girl refuses to travel with them at some point so she decides to pretend to be the girl so they can have a place to stay.

She has two real goals in England: find the man who impregnated her sister and secretly raise money for the union army to take home with her.

Her grandmother is cooky. She pretends to be different characters most notably Queen Maeve during the May Festival.

The hero is friends with the grandfather. He thinks the heroine is a teenage girl but finds himself attracted to her.

She goes to a church and a bookstore to collect funds from her "archangels" for the war efforts.

Scenes I specifically remember:
They first make love in a tent at the May Fair/Festival. It was to be for the queen and king of the fair and there is a lot of food in it.

He takes her and the sister to a botanical garden and he makes her ride a merry-go-round and she gets jealous when she sees her sister flirting with him.

At a dinner party, his friend's wife notices that she is not a young girl at all and tries to tell him. her children overhear her talking about having a baby by Thanksgiving and the hero thinks the heroine is pregnant.

She and the original girl (she shows up at some point) are kidnapped and held in a warehouse by members of the confederacy. Turns out her grandmother is a spy for the union as well.

Can anyone help me?

[Kris]

Kelsey, is this historical romance for younger or older adults?

Which war is mentioned in the book? What's the time period?

Who is the "younger girl", and why would the heroine help her?

Does most of the story take place in America or England?

[Lobstergirl, au gratin]

Kelsey left the group. Moving to Abandoned.