I wouldnu2019t say itu2019s right or wrong to be angry with them. But if it was me, Iu2019d say yes, itu2019s perfectly okay to be angry at them.You should talk to your friends about it, let them know about how you feel. If you donu2019t, then they might not know about your anger, or how they can fix it. It seems to me like this is a favoritism situation, where they like another friend more so they buy them a present for their birthday, but not for you on your birthday. In that case, talk it over with them, calmly and politely. If they are your true friends, theyu2019ll understand how you feel and they will do their best to make it up to you.If they blow you off, tell you itu2019s not a big deal, Iu2019d suggest you find new friends because they are not good friends. P.s- if they explain that they just didnu2019t have the money to buy something at the time, just tell them that itu2019s perfectly okay and you understand. Not everyone is rich, and sometimes they just donu2019t have the money for gifts. Just talk to them about possibly making up for it, and getting something for you when they have the money, or even just planning a day out together, like a beach day, or picnic, or even going to the park.Please just remember that birthday gifts should not cost a lot of money. Be grateful for what you get, even if itu2019s just a birthday card. I hope this helped you :)