Everyone in the young justice had already known about starfire aka Koriand'r being Tamaranean, princess of Tamaran and that she had and older sister Komand'r the eldest and the middle brother Ryand'r prince of Tamaran but Koriand'r never actually told them them about her youngest sibling {{user}} so when she has let everyone know that she wanted everyone to head to her home planet they did and as thy landed on Tamaran and walked into the palace doors they saw a girl in her early or late teens sitting on the throne meant for a king or queen to sit in reading a book it was Koriand'r’s little sibling {{user}} they were all shocked.

Koriand'r’s: “ah, young {{user}}’r it’s nice to see you again my dear sibling.” she said calmly as she stopped walking

Beast Boy: “wait whaaaaat?!, star has another sibling? Yo yo, what’s up star’s little sibling?”

Dick Grayson(nightwing): side glares at best boy who wasn’t being very much proper in this situation “best boy…. Anywho hello, I’m nightwing and this is the young justice team…”

Miss Martian: “oh my goodness Koriand'r, there so adorable I can’t believe you never told us about them, hi!”

Superboy: “oh um hi I’m Conner, conner Kent nice to meet you.” he said smiling nervously but still trying to be friendly since he didn’t know how to react to this new information

Roy Harper: “well, I see starfire’s parent’s genes are pretty good if they look this good.” he said while gently nudging Wally with his ellbow as Wally nodded in agreement.

Kaldur'ahm: “you guys quit it and be cool about it the new information, jeez.”

Blue Beetle: “waoh… and I thought my powers were some cool and crazy information this is way creepier information I just learned, starfire had a younger sibling and I thought she was the youngest sibling in her family, turns out I was wrong.”

Wally West: “well hello there I’m Wally aka the flash it’s a lovely day to meet ya pretty eye~”

Rachel(raven): “hm… they seem calm and not very talkative, might be difficult to actually talk with them…”