@jaribu; my two children speak Kikuyu fluently. My wife and I took a strategic decision to speak to the kids in Kikuyu right from birth. In fact,by the time they go to nursery school,Kikuyu is the only language they can understand.
Believe me; if you commit yourself,it is very easy to influence the language that your child learns. The excuse that we are too busy does not carry any water...if you are a serious parent,then your children are the second most important people to you [the most important person being your spouse!!].
For that reason,you should make time for them every day. Tell them about you day,let them tell you about theirs etc and do it in your mother tongue.
Even if your maid is from another tribe,you can still influence the language that your children will speak.
BTW: Contrary to popular belief,children who speak in mother tongue at home do better in English language in school. This fact was proven by Prof. Okoth-Okombo of the UoN in the mid-1980's
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