Hi
Going by the photo I´d say a girl...I have a way of sexing them at a young age and it seems to work 99% of the time.
The males bottom is different from the females, they have a more visible tail bone showing than the female, making a more pointier bottom.
Just like in Cane toads. I noticed when I got my male Bully then I got another which was supposed to be male but turned out to be a female.
I questioned the seller because the frogs bottom was rounded.
The baby has to be a healthy weight in order to tell properly though, if it is under weight the bones stick out on both sexes.