I don't know who I'm more mad at my husband or sister

We have a 3month old and I just went back to work. I had to go to Chicago for a conference for work for a week. My husband does a lot of overseas traveling to China. He was suppose to be home for a month so I agreed to go to the conference. My husband called me on the 2nd day saying he was on his way to the airport and that he left the baby with my sister. I tried to cut the trip short but wasn't able to. When I got home my poor baby had a diaper rash and hadn't had a bath since my husband left. She had a funky smell under her neck and when I cleaned it, it was like a paste from the formula and sweat.

I'm so pissed at my husband for leaving, I'm mad that my sister (who has teenage girls) didn't take care of my baby properly and I'm pissed that my boss wouldn't let me come home. Looks like I might need to find a new job.

* edit - my husband was suppose to be home he wasn't suppose to travel till the end of the month. But apparently work needed him asap. So it was a last minute travel plan. Either way I'm still pissed at him.