The penultimate chapter. It is filed under taboo incest, and runs about 6000 words. 4.8 out of 5 from 796 readers. Part 25 of Haunting of Palmer Mansion.

rawlyrawls also wrote La Belle Ile en Mere Pt. 28 and The Palmer Legacy Pt. 24.

Others under taboo incest Older Sister's Embrace, My Lingerie-Loving Sister Moves In and 2 Moms, 2 Sons... Ch. 5, and 9 more.

Or keep going.