Im just really wondering how those two turned into a Nobody. They weren't students of Ansem and/or Xehanort.

Most likely one of Apprentice Xehanort's experiments regarding hearts and doors.  If you watched Kingdom Hearts 3D cutscenes, it shows him striking down Braig, which probably happened to Lea and Isa also.

 

In Birth by Sleep, they also mention being ready for something and look up at the castle, symbolizing them probably going there to do something significant that set in motion a chain of events that led to their demise, creating Axel and Saix in the process.

 

Lea and others also wake up in the lab after being reconstructed/recompleted, implying that they lost their hearts somewhere in Radiant Garden.  Restrengthening the theory that they probably suffered through the same trials.

Edited July 24, 201312 yr by Prince Sky Heart

It's never said but we are given clues . We see them getting kicked out of the castle in BBS after trying to sneak in. Since Lea revived in the lab they must 've been part of the experiments ( they prolly tried sneaking in again later down the road and were caught and possibly forced  ) and we know the apprentices were experimenting on townsfolk so put two and two together and you get ...lol . Hopefully KH3 will expound on this further.

Edited July 24, 201312 yr by Flaming Lea

They were stabbed by Xehanort when he was on his stabbing spree in the castle.

They were stabbed by Xehanort when he was on his stabbing spree in the castle.

How do you know ?:$

They were stabbed by Xehanort when he was on his stabbing spree in the castle.

Stabbing spree?..lol

How do you know ?:$

 Let's see here .. Lea revived in the lab and you revive where you lost your heart .. He was wearing a cloak at the time he lost his heart ...One could say they were forced into the experiments and since the apprentices lost their hearts  and joined the org before Lea and Isa they prolly knew to put cloaks on them before they were stabbed in the experients bc they knew they would need them . Like I said , you can gather this from what clues they have shown and theorize . We just don't know for sure 100 %

Nah, Lea and Isa probably needed summer jobs so they decided to work for Ansem and got all firetrucked up in the process.

I wondered this. Thanks to everyone that answered.

They were struck down by Xehanort. Most likely being in the wrong place at the wrong time.

I hope we find out in KH3...it would answer some of my questions about Lea's age...