Hello,

I'm writing to you because I'm concerned with a situation I'm in and I wanted to hear your advice.

I'm finishing the second year of my PhD, which it turned to be a continuation of my Master's work. During my Master, I did research with my Master advisor and with my current PhD advisor. We have continue to work together and to publish papers during my PhD; however, my PhD co-advisor has not participated on any of them, not because we did not want to, but because he is always busy with his work. The only publication I have with him is a little paper I wrote for a PhD symposium.

What do you think? Is it normal to do a PhD while publishing with people other than the co-advisor? Is it going to be weird or could I have problems because of that at the end of the thesis?

I would go to your supervisor and discuss this matter. If the work your are publishing isn't part of your PhD, and your PhD superrvisor isn't involved, then I don't see an issue there. If anything, your supervisor may request that you spend more of your time on publishing papers from your PhD.