Sharing Our Innermost Thoughts

Just found that my dad is cheating on my mom. She knows it, but doesn’t have the strength to accept it. Though he refer those girls as sisters, but the chat my mom saw was going another way. She knows it right. Just that she’s broken to know about all this and doesn’t want to talk to anybody about this. We went through the dad’s phone too. But the chats those were there right in the evening, doesn’t exist now! He deleted them. This isn’t the first time he’s into this. I can understand her pain, it hurts to see your partner cheating on you. I can feel her. But I have no way! Is there any way I can get those chats and call logs back? I don’t want her to suffer. Though we can’t move out, but ig there’s nothing wrong in making him realise that not everything he does is correct!