Really disappointed with LaSalle (spoilers)

Well not so much with LaSalle, but the writers. They've made him look like a complete prat with this whole baby daddy nonsense. I find it hard to believe that any man, let alone someone with the smarts he supposedly has (and access to DNA testing lab), would just take her word that he's the kids father. It's a bloddy ridiculous story line and I can guess where it's going.