How do you handle a family member who's constantly seeking compliments?

Usually people who behave in this manner have very low self esteem. They do this to make themselves feel better. She most likely does not have the self confidence you and your sister have, since she came from somewhere where she always had less. It could be that she is also a little jealous of you since you have lived here growing up with a nice lifestyle and no worries. Why don't you try talking to her about it? Maybe doesn't realize that she is coming off as a "show off". Let her know that you are her family and that no matter what you care about her and love her and you don't care about the material things, you want to know how SHE is...not what she is doing or accomplishing. Tell her that with you she doesn't have to try to impress you with these things, that she can just be her true self. Hopefully the message will get through to her. Good luck!