sisterhood

No, sorry. There is no "strongest sisterhood". Sisterhood is what you make it. If you don't devote yourself to the sorority and make connections, you won't have a strong sisterhood, but if you give it your all, your sisters will love and respect you. There's no one sorority where everyone gets along. In a group of almost 200 girls it's impossible that everyone will get along. I would say all of the strong sororities have good sisterhoods. I am in one of those sororities and I love my sisters and have seen them be there for each other when sisters needed them and it really warms my heart. But there are always a few sisters who don't spend much time at the house and then they obviously have less of a bond.

My point is, anyone NOT in those sororities will probably tell you that they're all bad (because they're the competition obviously), but really, it's what you make it.

All the KDs I know hate 90% of the other KDs. I've heard the reoccuring joke over and over "Even KDs don't like KD". That could just be slander but idk. The few KDs i know have all said negative things at least once to me.

My roommate is in ZTA and she says that despite their bad rep they actually have a really good sisterhood and the newest PC in particular is really close.

I am not in any of these sororities so I am just telling you what I have heard on greek row. I don't have facts to back it up, so take it with a grain of salt.

usually top tier girls have the worst sisterhood thats just from what ive seen.

Well I don't think there's anything wrong with knowing information about a group of girls you may actually end up with. To me it's important to hear things because they do help guide you. Sometimes a sorority could have a bad rep and you may feel at home but then after you're already in you may hate it because of what people think of you because of your sorority. Still this site is effy for information. Anyway
KD is effy. A few friends love it and a few friends say they hate it and wish they were with another group
ZTA has a bad rep but a lot of the girls I know actually love it. I haven't heard many that don't.
TRI same with ZTA but they don't have a bad rep