Maya Soetoro-Ng, right, poses with Nia Alsop, 7, at the author’s visit to the Tenley-Friendship Neighborhood Library to promote her new children’s book, “Ladder to the Moon.” (Mark Gail/The Washington Post)

No denying whose half-sister she is: Maya Soetoro-Ng has the same earnest-calm manner, the same lofty rhetoric punctured by flashes of dry humor. She and President Obama must have got it from their mom.

Ann Dunham, who died in 1995, is the central character in “Ladder to the Moon,” Soetoro-Ng’s first children’s book — but already the second to come out of this first family, following her brother’s “Of Thee I Sing.” “Ladder” tells the story of Soetoro-Ng’s daughter Suhaila, 6, and her yearning to know “Grandma Annie.” One night, a golden ladder appears next to her bed, and the little girl spends a magical night with her grandma on the moon.

Soetoro-Ng shows off “Ladder to the Moon.” (Mark Gail/The Washington Post)

The teacher and her family are now back in Hawaii after a brief stint living in D.C. in the first year of her brother’s administration. She said she wrote the first draft in a day, then began editing while artist Yuyi Morales worked on the illustrations, a process that took more than three years.

Early reviews: The president “said it was sweet and captured our mother’s spirit nicely,” and Suhaila gave it a big thumbs-up. “She reminds her first-grade class all the time, ‘My name is in the book.’ ”