Leaving a 2 year old for ten minutes?

Alright, so here’s my question.... I’m a full time nanny and got a new shift with the parents. They have me put the two year old down for a nap around 1:30 PM and have me pick up the older sister at 3:15 PM. The parents told me to leave the little one sleeping in the crib while I pick the older one from school. The school is less than five minutes away. I would say I’m gone for a max of 15 minutes and the parents watch the baby on the camera while I’m gone. I feel uncomfortable even though their parents are telling me to. Can I get into trouble for this? Is this a normal thing? Let me know. Thank you.