Terrible at daytime naps

My 4.5 mth LO naps really terribly in the day and only willing to nap for longer periods when we are carrying her. Once we put her down in her crib she'll be up in 15 to 20 mins. She sleeps through the night fine though, so is this considered sleep regression? Anyone has tips on how to keep her asleep longer in her crib? Should I get a yaolan? #firstmom #firsttimemom