I had to bring up to my son about the gay porn on the tablet

My kids all share a tablet. Sons are 15 and 8, my daughter is 6. I ended up finding gay porn on the tablet. I automatically assumed it was my 15 year old. I took some advice and decided to just let it go and put a parental lock on the tablet. He mainly only uses it for the kindle app anyway to read books. I have no idea how but one of the kids (I'm assuming him) managed to hack the lock and get it taken off. How I found out was my 6 year old came up to me and asked about videos she found on the tablet. And it was more gay porn. I took the tablet and knew I needed to speak to my son. One mistake I made was I probably should have just said porn. Because the second I mentioned to him that I found gay porn on the tablet he started crying. He was saying he was sorry and that he's not gay. I tried to explain that I just don't want him watching any porn, especially on a tablet he shares with his younger siblings but I couldn't even get that out because he was asking me not to hate him. I'm just gonna have his dad talk to him. Maybe this is a male conversation best had with another male