Let me advise those of you young people in the corporate world.
If you have a colleague that both of you were mates in rank or position, and you were very close, and that colleague of yours later becomes your boss.
Do not say because you were once mates in position, then you think you can interact with him or her the same way.
Respect the authority that he or she is presently occupying and keep your distance.
Wait to see if he or she would still want you to be closer, before you know how to interact with them officially.
Your bosses take key decisions for the firm, even if that decision may affect you.
They have meetings that you're not privileged or qualified to attend.
If you keep trying to interact with that colleague simply because you were once close, you'll be shocked.
Where they're making decisions that may affect you, your once close colleague may throw you under the bus.
Especially if you work in a structured environment, where meritocracy is recognized over familiarity.
Your colleagues are mostly not your friends.
All of you are earning salaries just to get by.
Do your job diligently, so that your once close colleague that was at your level, will not be seen as trying to use his or her position to favour you unduly.
I didn't write this posts for illiterates or ignorant or entitled persons.
End.