Plus what about brothers and sisters? I have to laugh about this question because you are so sincere but there really is no issue. Heck, as the father of four kids let me tell you that privacy and modesty are unknown luxuries when you have several kids. One or another is aways wanting something when I or my wife is naked. Natural nudity - they type that happens when you live together is not only normal it is healthy.
Being a parent is not an easy task. Recently a father recounted his experience with that exact situation on Reddit. I very quietly made breakfast, went back upstairs and told my wife, son and other youngest daughter to be very quiet because people were still asleep. Our dinner table is on the other side of the room, about 20 feet from the couch but right in front of it. I pulled out the chair beside me.
Children's teenage years are supposed to be full of learning and laughter but one man has spoken of the unimaginable abuse he received at the hands of the person he trusted most - his mother. The woman who he described as 'mentally unwell' had sex with him one day when he was recovering from sickness. An Australian man has told the horrifying tale about the sexual abuse he received at the hands of the one person he trusted most in the world - his mother stock image.
Vague question, but I'm assuming your his mom and that he's a teenager or older since any other situation wouldn't warrent a question. To that question, I'm a single mom of three boys and after about 9 to10 they became a bit shy and always closed doors around the house. For a few years I never saw any of them nude. We did some camping and a few times I'd comment, "you know, you boys don't have to run to the outhouse, you won't offend me if you just pee. Latter at home, once I suggested, "the neighbors can't see in our yard, if you guys want to you can pee in the yard when your outside.