General question and your personal experience about stuttering (my 2 1/2yr old)?

So my 2 1/2 yr old has always been pretty verbal, articulate and able to pronounce all her words. About a week ago, she began to stutter the beginning of some of her words. This is the thing, she has been around her cousin (age 5) who has severe stuttering problems in recent weeks. I'm thinking she picked up the stutter (as children copy other children behaviors) or maybe it's some temporary issue (as most websites have reported). There is no physical indication she is struggling to get the word out, it just irks me. What do you guys think? Is she copying her cousin? No need to panic? Thanks for the feedback.