Momsh, based on how you're describing it, started hard and may have had pus, now softer pero may redness pa, sounds like it could be a cyst or skin infection na nag-improve na talaga, kaya better to have your pedia check it out just to be sure it's healing well and walang risk of infection ulit. A few of us moms had similar bumps sa babies namin na nag-clear eventually once treated, so it should be fine, pero doctors can tell in one quick look kung okay lang or if kailangan ng anything specific!