DC is almost 3 and I have now tried EVERYTHING. NOTHING has worked. No safety harness, nothing. He can just escape them all.
Even tried a different car seat of a friend (a cybex, it has this installment instead of straps) and he got out of that too. Not sure where we go from here...
I'm at my wits end. He's a lot of hard work and getting out and about with him was my only saving grace at times 
Does anyone else have experience of this?