L.S.
My almost 4 yr old was the same way. She had very short naps (even at daycare, she went to daycare from 6 mos to 15 mos). Eventually, at about 14 mos she took 1 longer nap, and she started napping every other day at about 2 years old. She completely stopped naps shortly after (unless we had a long day out, we were driving, etc. she would nap in the late afternoon). She has always been a fabulous night time sleeper so I didn't worry about the naps since she is such a happy, well behaved child and she sleeps good at night.
I now have an 11 month old, her naps are also short and she sleeps very well at night and she is also a happy, spunky little girl. The cat naps are just what suits my girls I guess!