When I had my 02 TJ putting my 1 year old in the back was a PAIN, unless I had the top off, it was lifted on 37's. But it wasn't my daily driver either. The kid loved the jeep!!!
I just recently purchased a 2014 JKU and now that I have TWO carseats, there is NO WAY i could do it without a 4 door. My oldest is almost 4 and youngest is almost 2 and they are both in forward facing seats. Of course, the little guy is behind me because he's got short legs!! I love my new JKU and it's now my DD!