So we visited our family doctor on Monday and Mataya has fallen off her growth curve for weight. My doctor wasn't too terribly concerned at this point. He said that she looks like she is healthy and thriving and if she is sleeping that well she must be feeling satisfied. He did want us to come back in month to have her weighed again, but he didn't recommend any changes in the mean time.
So we will carry on and I am really not too worried either. She will be starting solids soon enough and if she is anything like her brother, she will really fill out then. In Canada, the recommend waiting with solids until 6 months, but in the States they say you can start as early as 4 months. I started Joash at around 5 1/2 months, so we will see how long I wait with her.