Regular day naps but irregular nights

My little girl turned 4 months old on the 13th. Lately she’s been sleeping every 1.5 hours during the day. But only gets about 3-4 hours during the night. I don’t think it’s a leap. She used to sleep through out the night before I switched her into her crib at 3 months. And now it’s only 3-4 hour stretches. Is there anything I can do to help her? I’m pretty consistent in our routine; bath time (depending on the day) diaper change and jammies, then nurse and put down.