Why does my 8 year old daughter have a pop belly?

I am concerned about my daughters belly.  She is a very active young girl.  She's in a basketball and swim team.  Her body is very fit and slender,with an expection of her belly.   She is becoming aware of it and is embarassed about it especially when she is in her bathing suit.  She sometimes looks like she is 6 months pregnant.  She's at 86% in her growth chart.  She weighs 76 lbs, is 4'2 tall and is 8 years 9 months old. Im not so much concerned about her looks like she is, but I am concerned that she might have parasites or something. Is this normal for her to still have a pop belly? Both my husband and I are obese so we are wondering if maybe it could just be genes.