I didn't catch him doing anything. He was watching some news thing on his laptop & wouldn't let me on it to play Runescape.

My mom came home from work, after he'd left for his work. I told my mom he'd been watching gay p0rn because I was still angry.

This morning she's been really b*tchy to him but I'm sure she's not said anything to him because he keeps giving me confused looks. I feel bad for him now but I can't tell the truth because my mom gets hysterical over anything. What can I do? Tell him or what?