Transcript for Woman allegedly suffering from multiple illnesses arrested for mom's murder
Reporter: Two of Springfield Missouri's most renown and revered citizens, gypsy Blanchard and her mother Dee Dee taking center stage. ??? I believe there are angels among us ??? Reporter: At a relay of life event to raise money for the American cancer society. The reason I was born to be a mom. Reporter: But the sickly and often secluded gypsy believes she too has found her guardian angel. Not at home in her mother, but online with a man. Nick godejohn. She was in love with him. She thought that he was going to be the prince that came and finally saved her. And got her out of her locked tower and they'd live happily ever after. Reporter: Look at some of the messages the love-struck teenager sends a friend about her prince charming. I met a wonderful guy. He's my first boyfriend. He gives me poems and is so romantic. She was talking about this new guy that she was now in love with, and that they had met on a Christian dating site and that they were already planning on naming their children after him. We want a snow wedding in a gazebo with red and white roses. Honestly, what I was thinking whenever I saw these messages, is that these were just like fantasies and dreams. Reporter: But on their shared Facebook page, the harsh reality is what people saw. Dee Dee presented as a very doting mother. This was her child. She knew she was sick, and she was just going to love her. Unconditionally, until she couldn't anymore. Reporter: But then comes the day when family friends, Kim and David, are horrified. When something very different popped up on gypsy and Dee Dee's Facebook page. A very vulgar post. It said the bitch is dead. I, instantly took it as, their Facebook account had gotten hacked. Then we saw the second one, which said, "And I raped her sweet daughter, too." Reporter: Kim and David race to the little pink house. No one seems to be home but their new car is in the drive way. We circled the house, knocked on all the doors and windows. I called the police and let them know that we needed a wellness check done on a disabled mother and daughter. And they said that they would send somebody out. Breaking news. The body of 48-year-old Dee Dee Blanchard has been found. You just can't forget the pink house with the wheelchair ramp. I see a stretcher coming out of the house and I just sobbed. We found Dee Dee Blanchard deceased and of a violent nature. Still actively looking for gypsy. Then we really panicked because oh, my gosh, somebody has kidnapped gypsy. Tell me about the moment when you heard that something happened to Dee Dee and that gypsy was missing. I was shocked. Couldn't understand it. Why would somebody do this to this child? No wheelchair. No medication. They gonna just leave her for dead. Reporter: Authorities move quickly and hit pay dirt when they trace the ip address of those profane Facebook posts to a small house 600 miles away in big bend, Wisconsin, at the home of Nick godejohn. Gypsy's boyfriend. Who is Nick godejohn? He's functions at about 15 or 16-year-old. He is a kid that is similar to gypsy from the standpoint of not really having a Normal social interaction history that most kids would've had up to that point. They go to the house. There's some standoff for a period of time. They have to bring the S.W.A.T. Team there. Reporter: When authorities enter the home they take both into custody. We started hearing from various sources, that gypsy wasn't a victim. She wasn't kidnapped, that she was actually involved in this somehow. It was very shocking beyond shocking. We have located gypsy in another state. Uh she is ok. Uh we do have another person of interest in custody. I'm detective Hancock. Your mom is dead okay? Now what I want to ask you, did you have involvement in this? Wait, go back. What? Your mom's passed away, okay? She's deceased, all right? Now, what I want to ask you, did you have involvement in this? No. No. What happened with your mom that night? I don't know what happened with my mom. I don't know, why don't you just tell me? I don't know what happened with my mom. I don't know, why don't you just tell me? Just listen to me, okay, sweetheart? You know what happened to your mom, okay? You know exactly. I'm not going to play around with this. Sir, I didn't do anything! Reporter: While gypsy keeps mum in the interrogation room, what does the other one say. From what she told me, her mom kicked her out of her house.
This transcript has been automatically generated and may not be 100% accurate.