In a fiction world, yeah, totally, go nuts! Make all the Spinosuarus Rex babies you desire. I ship LittlefootXCera, so who cares.
In a realistic world...yeah, maybe not. The T-Rex and the Spinosaurus were two totally different species, the Spinosaurus not even being a Tyrannosaur or in the same family as the T-Rex. That being said, both species were reproductively isolated from each other due to biological boundaries. Simply put, I don't think it would work. Even if, by some miracle, the two did happen to have an egg, it's highly unlikely the egg would hatch and, if it did, the offspring would not be viable.
If, per se, you happen to get another type of Tyrannosaur, that being in the same family as a T-Rex, like maybe a Gigantosaurus, then it may work. Think of it like a mule, produced by a Horse and a Donkey. Maybe it would work, but then the question is whether or not the offspring is viable. But, as the saying goes, nature finds a way.