I was wondering if there is any fixed expression, poem, proverb to imply:
Every one who is left far from his source (source= his / her tendencies,) wishes back the time when he was united with it.
I.e. You will always have a tendency to become what you are and not what you are trying to be! So, you will revert back to your essence one day.
Please imagine a young person who loves music composing field of working and wants to be a composer at heart. However, despite their feelings, their parents want them to become an engineer. They may get even a university degree at engineering just because what his/her parents want, but usually, they will revert back to their own interests and probably will work as a composer even as their second job one day! Because this is the field that they belong to and enjoy it.