Receiving money from a will.. is it taxed?

My grandfather ped away in 2005. He left a little over 10 grand for each of his grand children to receive after they turn 25 years old. The money was left for my uncle to oversee. It was put in and eventually (2009) cashed out of stocks. My uncle mentioned taxes paid on the money. It is over 13 grand now. Now that I have turned 25- he wants to mail me a check for the total sum of the money altogether. So my question is if this has to be reported to the IRS or if more taxes will have to be paid on it. Or if there is a way he can transfer the money to me to avoid or decrease the amount of taxes etc. Thank you.