We stayed with our 22-month old daughter in Inês & Koen's beautiful home. It looks just as lovely as it does in the photos, and is spacious, light and airy. They had lots of children's toys and books, and our daughter loved playing with the toys and wandering around the apartment. It was quiet at night, and we all slept well.
One thing to note is that there is no elevator. This was not a problem for us, as our buggy was light to carry up and down the stairs. We didn't spot a baby bath or changing table, but we didn't particularly need these and we didn't ring to ask as it wasn't an issue for us.
We had a wonderful stay and would definitely recommend this place to anyone visiting Lisbon, with kids or without!