Can't get my 14 week to stay awake for longer than an hour

[moonagedreamer]

All the books say that baby should be staying awake from 1.5 - 2 hours as you approach 4 months. I've never been able to keep my little girl awake for more than an hour and then she only has a small catnap of about 25 minutes. She gets really grumpy at an hour, constantly rubbing her eyes and yawning. Do I just let her cry to keep her up longer and therefore lengthen her naps?