It's not self defense, and no threats were made. Boy didn't break in either. This won't end well for dad and daughter.
I think you have to go on what info the Dad had at the moment. As far as he knew it was a break in and I think Tejas has the Castle Doctrine. He may walk but they get the daughter on some sort of manslaughter type charge.
A break in where the intruder is in bed with the daughter and the daughter invited him in? Don't think so. I just can't see where any of the self defense laws can support the actions of the father. No threats to ANYBODY in the house but he shoots the kid. Not seeing how this is self defense in any way.
The daughter first claimed that she didn't know the person and that they weren't in bed. He told the kid not to move and the kid (supposedly) did move and got shot.
I wasn't there so I'm just speculating but IF there is a stranger in my daughters room at 0200 then his ass better freeze when I say freeze. I gotta tell you, having been to Houston that would be one hair trigger too. Also having been that teenager I would have been so "froze" they'd have to take me out of that neighborhood with a set of hand-trucks.
Probably a dozen different ways it could have turned out with this one being one of the most tragic.