I too seperate lights from darks - especially if there is red clothes - i just don't trust it...we're not a huge fan of pink on boys. If I only have a few items i'll combine (even if there is dark blues and black- just never the red item - regardless of how many times they've been washed). I also now wash their clothes in with mine. When DS1 first arrived I would only ever wash his clothes on their own and in baby detergent....by DS2 - it started for the first weeks with DS1's clothes only - but after a few weeks I ended up combining mine in (and occassionally DH's - but he gets grubby and works with trucks - so his gets collected all together for a load of their own). In the end you'll end up doing whatever is easiest and will get the job done (well that's how it is with me ).