My son has and is in the 99% of head circumference...in 100 kids there is only one whose head is bigger than my baby!
Our previous doctor in CO was not concerned...as even in utero the kids head was gigantic. Even after a cyst on his brain was detected at 17 weeks gestation. (it went away and no sign of it since)...
Moved to MO and new doctor monitored it for year as she had concerns. We kept telling her that it's nothing to be concerned about it's always been big. Needless to say she said ok...let's watch it for 6 months...then it was how about another 6 months."
Finally at his three year check up said ..."I'm in your camp, he just has a big head"...
If you looked at him you wouldn't know...and he's perfectly healthy.
My only advice is once she's a walking, running make sure she doesn't run/walk with her head down...my baby would fall all the time cause his head would roll him over.
ETA: yes shirts cause huge problems...the ones I can get over his head are huge on him. He wears a lot of button downs.