I'm not a parent, so I can't comment much on the parenting part, but regarding languages, I would say don't worry too much about it, just communicate more with her in BM

When I was in Standard 1, I knew not a single word of BM other than 'Nak pergi tandas.' However, being in a government school, I managed to pick it up quite well by having to interact using BM on a daily basis.

Mandarin however, I never quite managed to pick up... hahah