My husband (37) took his nephew (12) in after his dad (my husband's brother) was diagnosed with cancer. He told me that his nephew would be staying with us til his dad completes his chemo treatment. I agreed although he did not consult me about it first. but I told him that he'll be his responsibility not mine.
He asked me to explain why and I told him it's because 1. He didn't consult me before taking his nephew in, and 2. I'm not equipped nor experienced in taking care/being committed to child care. I still have to cook and clean obviously. He said it was fine and that he'd be taking care of him on his own.
The other day he called me in the afternoon saying he was stuck in a 2hr meeting and asked if I could go pick his nephew up from school. I said I was having lunch with mom and discussing family issues. He insisted but I reminded him that he said he'd be taking care of his nephew including school pickup/dropoff.