Didn’t Know General Was Female [Rebirth]

Rong Jiahui, who choked to death on a slice of winter melon, thought she would descend to the underworld and reincarnate. But when she opened her eyes again, she was horrified to find herself back twelve years in the past... Staring at the beautiful yet prickly "little brother" before her—who in the future would earn illustrious military merits and rise to nobility—she nearly laughed out loud. She decisively resolved to cling to his thigh and never let go, soaring to the pinnacle of life! The plan was indeed perfect—except, somewhere along the way, something went wrong. How did this little brother suddenly become... A sister instead...?