Is it ok to be a little upset that my b/f gave his EX g/f jewlery as a xmas gift?

he and i have been living together for 6 months and he and his ex are still friendly, they talk on the phone on often,,,,do ya think there may be more to it than just a friendship? am i doing the right thing by not saying anything and just let it be or should i say something that may cause an arguement so near the holidays?