I spent there 12 days in late December and early January with my wife and our small daughter. Laetitia is a really nice person and very helpful, she always answered all our questions.
Apartment is in a charming old house with a narrow staircase. It is confortable, well equipped, and really QUIET (even on New Year Eve - big plus if you are traveling with a kid). The heating works well. The nearest supermarket is just 2 blocks away.
The biggest advantage is the location. Majority of tourist highlights in Brussels is in walking distance (just 20-30 minutes away): the city center and museums on Royal Place, Dinosaurus museum and EU district, Horta museum and other art nouveau houses in Saint-Gilles district, and a train station Bruxelles-Midi from which trains are going to the airport, Brugge, Ghent, Antwerp etc.