Yes it is. The skull is fairly soft at this time. It will go away.
I don't want to freak you out, but my son had a lump on the side of his head at 6 mos. and the doctor told me to not worry about it. I wouldn't let it go and wanted to see a pediatric surgeon. After the referral and appointment wait time I'm glad I was persistent. They had scheduled out of hospital day surgery and it ended up that they had to call in a pediatric neurosurgeon because the lump (tumor) had invaded the skull and cerebral-spinal fluid had leaked into his head. Watch the lump. If it increases in size rapidly, demand to see a specialist.
Are you talking about the fontanelle (the top of the head "soft spot" where the skull plates come together) bulging?
That's serious. It's fluid buildup on the brain that causes the skull plates to bulge.
Or, it could be a normal misshapen head caused from the delivery process that will round itself out soon. If this bulge is new - and the doctors in delivery didn't see it - she needs to take the baby in to the pediatrician or emergency room asap.
Here's a link describing what I'm talking about:
https://health.google.com/health/ref/Hydrocephalus