This is a great place to stay whilst in Berlin!
We were two adults, a teenager and a 2 year old staying for 4 nights. There was a solid internet connection to the teeanger, a large and lovely and closed off playground - literally in the backyard. There is direct access from the kitchen to the backyard and the playground, so you can keep an eye on the kid from there. There are plenty of very fine take-away restaurants around the corner, so if you have to eat at home because of small children, it's easy to find good food to bring home.
The flat in itself was in very good condition and perfectly clean. The host dropped in to say hello shortly after we arrived which was a nice touch. The area is full of playgrounds and parks, great cafees and creative shops.
We highly recommend this place, especially to families with 1-2 small children!