Calculation of calendar days Is the day a child is born counted when calculating the calender days for his birthday? For instance, Kadogo was born on 4th January 2009.How old was he on 4th March 2011?

In $4$th January, $2011$, he'll be $2$ years old. After $59$ days, i.e., in $4$th March, he'll be $2$ years $59$ days.