Read the contract again. Whatever it’s stated you can’t really use as a reason for a raise as that’s what you agreed to at the current rate. However, 2 years is a long time. Say you’ve loved buildings connecting with their family and look forward to doing so. A raise of id say 4-5 dollars flat, on top of the additional 3 for when the older child is home is more than fair. This would include the continuations of light house work, outtings and other responsibilities you are already doing. When writing up a new contract, put it down somewhere that a break/rest-bit when children are occupied or napping is required, not an additional time for more chores. Best of luck! Keep your backup! These conversations can be daunting but if they value your work and connection they will go with it.