What kind of vibe are you going for with Oren's sib? Do you want it to start with a vowel? Be two syllables? I could rattle off a dozen Hebrew names for ya, but it'd be better to narrow it down. Personally I love the name Oren, and it's on my own list of maybe-baby names. I like Dalia and Odelia with Oren.
Oren is such a distinguished choice - how absolutely lovely.
I worked with a girl once with kids 0rrin, Yum@, and I@n. So I'm sure you'll find something perfect for a second child.
Adina (delicate, gentile), Eliora (god is my light), Hadas (myrtle tree), Nava (beautiful), Shiri (my song), Tahlia (dew from god), Ziva (bright, radiant)
Alon (oak tree), Aviv (spring), Boaz (swiftness), Elah (oak tree or terebinth tree), Elior (god is my light), Noam (pleasantness), Tomer (palm tree)
(I just noticed that I seemed to have honed in on a "hebrew tree" theme there. hahaha. )
Love the name Oren!
GIRLS: Lilah, Noa, Sari (1st syllable pronounced "sare," as in the name Sarah. 2nd syllable pronounced "ee."), Tamar, Tikvah
BOYS: Amiel, Ash, Asher, Eli, Japhy, Jonah, Lev, Liev, Malachy, Obadiah (you could call him "Obie" for short - I think Oren and Obie would make a really cute sibset), Omri, Shai, Tobiah, Tobin
Great suggestions everyone, thanks!