Everyone and I mean EVERYONE at some point in their lives has felt some sense of envy
It is a quick natural response we innately have as humans when someone possesses something that we desire, a skill, success or qualities this is due to our feelings of lack in comparison to that person.
Now when envy is activated in friendship this is where things can get tricky. Your friendship can begin to experience tension and or conflict. Tune to hear more on this topic.
The research I referenced was from (Tandoc, Ferrucci, & Duffy, 2015).