What is slight down syndrome? Do you mean to say she is mildly intellectually disabled or does she have mosaic downs? Eitherways she needs special education expertise help. Our country's schools don't incorporate special needs in their education which is very essential for Down's kids. Try to enroll her to a special needs school as early as possible. Lemme know if you need recommendations. She won't learn the routine way other kids do so the most crucial thing with intellectually disabled kids is REPETITION. Like if you want her to remember her environment, you have to choose a specific environment first. And you do that not for a day or two but for weeks or months. Start from the path from her room to the bathroom then work to the next door house then the nearest supermarket etc.