Recent studies have found that for ells (english language learners), the most effective approach is:

The answer to this question is dual-language learning.
dual-language learning refers to the approach of learning another language while solidifying our primary language at the same times.
Parents could make this approach towards their children by getting them used to understand the meaning of each objects if translated into two language since the early age

Bilingual education is the best approach. This gives the learner a way to link the two concepts and languages together. There is a type of "transfer" that takes place between the first and new languages when both are taught at the same time, with reading in the first language leading to better achievement while being taught the newer language.