You simply can't...
No, because Mickey Mouse is not an actual person.
The mouse does not change. It remains a pointing and interface device.
Biologically no. But you could get a costume as Minnie mouse. Then yes
Prince
A prince
a mouse
the moon
he liked mickey mouse is why
He was Mickey Mouse
NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO
No, it is not possible for a Mickey Mouse fish to become pregnant as fish reproduce through external fertilization where eggs are fertilized outside the body.
The mice are very likely to fight and kill each other. Also, the wild mouse could have diseases which it could pass on to the tame mouse.