Not if a) his adult daughter was a resident of the home and b) she invited him in.
If she did not tell Daddy, the guy was an INTRUDER. If she didn’t tell BF that Daddy owned a gun, she was a fool or maybe was tired of the BF.
IF she ‘invites’ him in the middle of the night without informing her father - into her bedroom - and how did he get in? door or window?
She may b e an ‘adult’ but it’s NOT her home - if she wants to makes these decisions - she should have her own place - where SHE pays the freight. THAT give her bottom line decisions.
She had him sneak in - he knew he wasn’t supposed to be there. That’s why he ‘crouched in a corner’