Hi, my baby used to have short naps around 3 mnths old like that. After I start to breastfeed often, her sleep time getting longer, can stretch for about 2-3 hr. Also to make sure her sleep environment is comfy, not too warn or too cold. If your baby rook have aircond, can put around 25-26 deg C, depending on your baby’s tolerance. Hope this helps, take care!