When they left the room Heart started to move a bit her face showed of fear and she was sweating.
The Asriel woke up to Heart's whimpering he looks at her and sees she is crying he starts to shake her awake but it didnt help she started thrashing and she knocks the others off the bed they woke up but Sans he's a heavy sleeper. "Whats going on?!" Chara said angry, as he was woken up "I dont know, Heart started to thrash around and crying" Asriel replied with worry and fear in his voice. Chara had a face of fear and gets back on the bed he starts to shake Heart harder "Heart! Heart! Wake up, its only a dream, wake up!" he says franctice she wakes up with a start. Sweat is running down her face along with tears shes shaking she looks at her older brothers infront of her she hugs him crying even more.
They hold her close rubbing her back and rocking her back and forth "shh, shh its okay, it's over now no need to cry anymore" he says to her. Between sobs she says "I-I'm so so-sorry I didn't m-mean to wake you g-guys up" Papyrus gets back on the bed and hugs his sister with tears aswell. He got scared when Heart started to freak out like she did, Sans soon woke up to the crying and had his eye light showing when he saw Heart crying he knew she had another nightmare. He saw her white fox on the floor and grabbed it, he got on the bed and gave the fox to her. She looked at the fox then at Sans he gave her his signature smile, she smiled back and took the fox from him she hugged it tightly in her arms as if it will disappear on her. "Heart, can I ask you something?" Papyrus said, she nodded her head for she was still too upset to talk without stuttering. "Why do you always sleep with that fox? When we first met you had that fox with you the entire time?" He said, she looked at him then sighed and said "when I was younger, my Auntie gave it to me, she said that my mommy wanted me to have it as a reminder that her and daddy will always love me no matter where they are or if they are gone. So I always kept it with me and made sure it was well taken care of for it's all I have of my mommy, daddy and Auntie." She told him, he nodded his head and smiled "we should go back to bed it's late and we need rest." Chara said while yawning.
The others nodded their heads and went back to sleep. In the morning Queen Toriel came to wake them up, when she opened the door she smiled sweetly at what she saw. Chara and Asriel were on Heart's left side, Chara holding her and Asriel holding her hand. On top of her was Papyrus snuggled up, on her right was Sans holding both her and Papyrus protectively. She walked over and said softly "my children, it's time to wake up" Heart opened her eyes first and smiled at her mom she tried to get up but saw that she was trapped by her adopted siblings. She tried to wake them up but because of last night they were still tired, she turned her head to Chara and said "Chara I'm gonna est all of your chocolate if you don't wake up" Chara bolted up out of bed. Asriel falls off the bed with a loud thump waking up Papyrus and Sans with a start "no one takes my chocolate and gets away with it!" Chara yelled out, when he heard giggling he looked at his sister and frowned knowing that she did that to wake him up. "Ow, Chara that hurt why did you do that?" Asriel whines while rubbing his head. Chara looked st him and helped him up "sorry Azzy, I didn't mean to hurt you" Chara said apologetically to his brother. "Well, you really know how to make a wake up call, but seeing you like that is really out of CHARActer." Sans said " SANS! IT IS TOO EARLY FOR YOU TO BE MAKING PUNS RIGHT NOW!" Papyrus yelled at his older brother Heart, Asriel and Toriel laughed at his pun

"I'm still very curious on who this Lily and Night is?" Dr. Gaster said "well you can tell him, if you like, but if he experiments on you I will give him a bad time." Night growls Heart jumps a little to his sudden apearance. She smiled to his worrying she walks to a table and sits on it with a bit of a struggle. "Well, you can see if you like" she said. Dr. Gaster smiles and goes to her he gets the equitment ready and is a bit hesitant "whats wrong?" Heart asks turns her head to the side. Gaster looks at her and gives a nervous smile "I just worry thats all but do you mind if you show me your soul?" He asks Heart, she nods her head and shows her soul to him he looks at her soul in amazment.
"How - How is it posible that your soul is like this?" he says in shock Heart's soul is half red and half white Sans and Papyrus goes to the table to see and are amazed as well Sans more than Papyrus. Heart has a worried look and puts her soul away she then remembers she will never show her soul to anyone ever again. A few days have passed since that day in the lab, she still goes to Dr. Gaster because she needs a check on her magic since she is half human.

right now she is in waterfall with her siblings, "Chara, do you miss your family on the surface?" Asriel asked, Chara looked at him and glared he replied "you are my family now i don't need them they don't understand like you and the others do." Heart looked at her brother and understood what he meant, humans on the surface are mean especially to her. she was different from others and the humans didn't want to understand. 

"you know we only need seven human souls to break the barrier what if one of us got a human soul and we went to the surface to gather the rest we need?" Heart told her siblings, Chara looked at her and gave a smile. "that's a good idea, what if we went to the surface ourselves and got the remaining souls we need to free everyone!" Chara said with joy. Heart was happy and proud that she came up with the idea to free her friends and family. "okay here's the plan Asriel will be the one to cross the barrier, he will have my soul to do so" Chara started to explain "but, wait, how will you give me your soul?" Asriel asked. "easy i will die" Chara answered, Asriel and Heart were shocked to hear what their sibling just said.

"B-but i don't want you to die, i can't lose you too!" Heart said while crying, Asriel and Chara both hugged their younger sister comforting her. "it's okay, i will still be with you, just, Asriel will have my soul with him" Chara said while wiping away her tears. she nodded and Chara continued with the plan, a week later they had everything set up, Chara ate many buttercup flowers and ended up very sick. there was no cure for it and everyone was upset, Asriel and Heart started to hate the plan and wanted to stop it, but they were already too far into it to stop now.

when Chara's soul appeared Asriel took it and became an older version of himself. He took Chara's body and they went to the barrier. Heart stayed on the other side and waited for them to come back, a few hours have passed and Toriel came up to where Heart is sitting. "my child? what are you doing up here for?" she asked, Heart turned around and got nervous she didn't know if she should tell her mother the plan she made with her siblings or not. Asgore came running to the room looking very scared "Toriel! the children are missing!" he yelled. she looked at him in fear and turned back to her daughter she knelt down to her and asked "my child, where is Asriel and Chara?" she asked in a scared voice.

Heart looked at her mother with tears in her eyes and pointed to the barrier, her parents were horrified, she then heard her mother scream. Heart turned around and saw her siblings she smiled until she saw the blood on her brother. she got scared and ran to him, he fell to the ground and landed on the patch of buttercup flowers, "Azzy! What happened, why are you hurt?" she asked her brother in a scared voice tears runnign down her face.

He looked at her and gave a small smile "the humans thought i killed Chara and-and tried to attack m-me..... Chara tried to attack them but i stopped him, i-i didn't want to h-hurt anyone" he said while struggling to breathe, Heart saw that he was starting to dust and Heart knew that she will be losing both of her brothers. "A-Azzy.... please don't leave me" she said crying, he held her face in one hand and wiped away her tears. "it's okay.... i'll always be with you" he said then he dusted, Heart started to cry even more yelling come back.

sometime after what happened Asgore called for a meeting with all the monsters of the underground, declaring a war against the humans. He said that the next human to fall into the underground will be killed let it be man, woman, or child, Heart was scared and Toriel was repulsed by what she heard him announce. She told Heart to pack her belongings and come with her, she did just that and left with her mother, they fled to the ruins of the underground, there they lived watching when another human will fall down next and will try to protect them from the other monsters.