Yep

For us, there's not much to "handle" when it comes to our children and bi-lingualism. It has developed pretty naturally because the key ingredient with language acquisition and young children is environment. I guess environment is a key factor with ALL language acquisition.
I am from the States and my husband is from Hong Kong. We have lived in Hong Kong almost our entire relationship (except for a short stint living in Mainland China). Since my son (now 4-years-old) was a small infant he has spent considerable amounts of time with my husband's parents and his other Chinese relatives--especially before we hired a domestic helper. My mother came and lived with us in HK for about 9 months at one point and my sister lived with us for 6 months--other than that my son has spent very little time with my side of the family. My daughter is a year old and has met my mother, step-father and sister once.
My son speaks Cantonese very fluently and has from a young age (about 2-years-old). He is much more expressive in Cantonese than he is in English although he speaks really well in both languages and can translate back and forth between the languages (which he often does for me). He is in his second year of kindergarten at a local school where the medium of instruction is Cantonese but where he also spends time learning Mandarin and English from native speakers. He is learning how to read and write in both Chinese and English.
It's a collaborative effort for school work. I spend at least an hour almost every night doing his homework with him. I studied Chinese in university so at this point I can help him with the simple characters he's writing. My husband often also helps him with his Chinese. And at the grandparents' house they give him extra Chinese writing practice. I also work with him on extra practice in English and maths.
I would say at this point, my son's "heart language" is Cantonese because it's the language he turns to when he really wants to be understood or when he's alone playing with his toys.
My daughter is just beginning to talk intelligibly. Her English words include "milk", "dadda", brother's name, "mama", "bath" and her Cantonese words include "nai nai" (milk), "mao mao" (cat) and "bei" (give). She's a lot more vocal than my son was at at this age so it will be interesting to see how her language develops.
I think it is absolutely wonderful that my children can grow up bi-lingual and HK is a great place for it. It also makes my son more open to other languages and not intimidated to learn. Our helper is now teaching him some Tagalog phrases which I think is really cool too.