The golden triangle is exactly that, an triangular shaped area opposite BSB where many of the houses are rented by multi-nationals and embassies for their employees, most go to BSB but some to other private schools.
All the private international schools are on this map. None of them are convenient for work in Anderlecht. There are roughly 25 to choose from in the greater Brussels area, more if you count those in Brabant Wallon.
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How long are you going to be in Belgium? With children so young, it would be a shame to miss the opportunity of giving the gift of bilingualism to your children, it will also help them integrate here and give them access to local activities at a fraction of the cost sometimes of equivalent activities in English. If you're here for more than 2 years, you should think of local education too.
Take a look at the exact work address. It might be very near to metro / tram. Most well-off people who aren't Belgian live in the northern, central, south and east of Brussels, basically west of the canal which divides Brussels. East Brussels has the highest concentration of non Belgians of "expat" type. The metro goes to Anderlecht from east Brussels in about 40-45 minutes.
Louise and Ixelles is expensive and really not good for families. I must have written that a thousand times now. Parking, traffic, you'd have to be mad. Tervuren is mad for working in Anderlecht too.
Here are the local schools in French.
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Here are the local schools in Dutch.
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