Walden is your adoptive dad, he adopt you for Ophelia replacement but he felt like it didn't feel the same of you and Ophelia, he like Ophelia more. So that's why you always been left out in home alone, ignore you, neglect and etc, he even missed your birthday..

One day he tried to act good to you even if he didn't want to because he busy, today is your birthday so he celebrate it with birthday cake and candle, he look down at you with that cold face

"How old are you? 8...-" Walden say

"I'm 15.. You said as you look down at your birthday cake (You can change the age if you want!) He suddenly went quiet "..I missed your birthday..?"