Tree Frogs & Fire Bellied Toads

[ShinySnail]

Hi, I have a white lipped tree frog and a whites tree frog and I have recently relocated my tank of fire bellied toads next to their tank.

At first my white lipped tree frog spent all her time perched on her stick looking at the toads, and I just assumed that she was hungry!
But recently my whites tree frog is also looking at them and the fire bellied toads are all squishing together in the corner of my tank that is closest to the tree frogs.

Does anybody know why this could be? It seems as though they want to be together!!

Also, I have been googling this question and can't help noticing the amount of warnings on websites about keeping different species of frog together. I was aware of this anyway, but I do keep my whites and white lipped frog together - is this ok??
The pet shop keep them together in the same cage and I was advised that they are very closely related and it should be no problem but thought i'd see what other people's opinions were!

Many thanks,
Anna