Leaving my husband for a week? (SAHM question)

Soo my oldest daughter has this amazing opportunity coming up next March to go to Disney World with her class and I'm so excited for her! She really wants me to come a long to be a chaperone buutt by that time my 5 yo will be in kindergarten, my 4 yo will be at home a long with our baby on the way who will be 7-8 months by then..my husband always carries a bunch of PTO so my question is, is it wrong for me to want to go? Is it selfish to my husband and other kids? Should I just stay home and continue my sahm duties? What would you do?