Yes, very justified. Your workload is high and your hours are about to go up. Explain to them why you need the raise and be clear on your expectations as well.
Developmental levels vary with infants and toddlers and each child should be treated as an individual. % month olds should be building gross motor skills like walking and crawling. Having an activity that uses the babies hands or feet is key. I would recommend putting colored paint into a ziplock bag... more
When working overtime, time and a half is the gong rate. Each family is different but keeping an open line of communication is key. as longs you are paid for your work it is legal.
Make sure you set boundaries when it comes to your authority. It begins with the parents explaining to the kids that while you are there, you are in charge.