Depends on your expectations - there are three of us (Mrs FB, 8-year old FB Junior and I) and the DS4 has been an excellent family car, the only times it's ever been pushed is when we carry rear seat passengers behind me as I'm 6'4" and there is very little leg room but if I lift the drivers seat then my 5'3" wife can sit behind me; a family we met in the lakes a few years ago had a DS4 and three kids in the back but as the Dad was about 5'10" legroom wasn't an issue. Once FB Junior is out of a booster seat (imminent) then he should be able to sit behind me fine. I hasten to add that all cars in this segment would, to a lesser or greater degree, be the same - it's not DS4 specific. I don't really want a bigger car though, our old Picasso felt like a bus.
As kids my sister and I used to be ferried all over in my Mum and Dad's CitroĆ«n Visa Special which wasn't very big and had a 34bhp 652cc flat-twin!
Was; 2015 DS4 2.0HDi \'blue\' 150 DSport in Babylon Red with black leather (not missed)
Was; 2013 DS4 1.6HDi 115 DStyle in Gris Aluminium with Sao cloth/ leather (sadly missed)