Based on the song, "Just Gold" by Mandopony. c:
Again, kinda old art but, I still like it.

Let me explain.
When Danny was born, Izzy never cared about him. She felt like he would weigh her down and only be a distraction from her goals. So she just let Kristoff raise him. Jamie came in eventually and helped raise him as well. When he was about 14 years old however, he started to really develop his pyrokinetic abilities. Izzy didn't even think he'd get those from her but, when she saw he did, she immediately took him away from Kristoff. She wanted to teach Danny how to use his powers so she could later use him as another fighter later on. Another member to her already strong army of sorts. To make him leave Jamie and Kristoff, she had to pump him full of lies and false hope. Telling him that Kristoff and Jamie were holding him down and if he teamed up with her, his real potential would be realized and he could do anything he wanted. This false sense of power eventually got to Danny and he turned away from his father. She gave him money, power, and got him addicted to parties, drugs, and alcohol just like herself and she's the reason he's what he is now. So I felt like this song, or at least the chorus, was a good way of explaining this situation.

tl;dr: Izzy's a manpulative bitch who used her son for her own gain and to fuck with Kristoff.