Sort of. I worked with a family with toddler twins and a special needs 6 year old... I had been told in the interview that I'd rarely be responsible for the 6 year old; he was in school and had a private tutor/nanny after school. I'd only been with them 3 weeks when the private tutor/ nanny said she needed to drop from 5 days a week to 2 days a week with them. I spent a few afternoons with all 3 but it was really hard; the 6 year old was violent, unpredictable, and unsafe for the toddlers to be around and I really wasn't well equipped to handle him honestly, let alone all 3 of them. I also couldn't leave the house with all 3 kids. I told MB I didn't feel comfortable watching all 3 kids for more than an hour at a time, so MB asked the grandparents to help with the 6 year old on days when his nanny wasn't available.
The second day the grandparents were in charge of him, they arrived at the house and took the 6 year old to his room to play. I was getting ready to take the twins on an outing, packing snacks, etc. Then the 6 year old ran out the front door--grandma forgot to lock it on her way in. We all knew the 6 year old was unpredictable and the parents and I were always very careful about locking the door, and the grandparents were well aware of this, too. The 6 year old was lost for 3 hours, police were called, etc. He was found safe in a neighbors yard that afternoon. MB let me go that day with no notice. She said she didn't feel safe with me in charge of her kids. I found that very infuriating, since I'd been told from the beginning I'd rarely be watching all 3 kids, and I'd been told very specifically that the grandparents were responsible for the 6 year old that day, plus grandma admitted she had been the one who left the door unlocked; none of that was my fault. But I guess she couldn't fire grandma, so MB fired me.