"My boyfriend's young son is sexually inappropriate, but my partner thinks I should ignore it."

A distressed woman has submitted a post to online forum Reddit in an attempt to resolve an issue with her partner and his young son.

While the post has since been deleted, on Monday the woman explained that her boyfriend’s 13-year-old has Down syndrome, and has always been particularly affectionate with her.

“The son has always hugged me a lot when I see him and my boyfriend and his mum (the grandma) are always like ‘oh how sweet! Oh he loves you!’ stuff like that,” she wrote.

But one recent incident left her very concerned.

“The son was hugging me and kind of straddling me and pressing his groin on my leg and it felt really inappropriate to me and kind of like something was going on in the groin area,” she shared.

Then, he went to the bathroom.

“The son was in the bathroom changing for a long time and my boyfriend opened the door and said ‘oh s**t’ and said he was peeing, but I thought that wasn’t really what happened.”

"Anyway the son came out and then gave me another hug before he went to the pool and it really felt like something was pressing on my leg."

Eventually, her boyfriend admitted that when he walked in on his son in the bathroom, it looked like he may have been masturbating.

"Now I feel totally grossed out," the woman wrote. "In retrospect, I think this has always been going on and is why the son likes me so much. I always had a suspicion that it felt like something inappropriate was happening when the son would hug me but I told myself ‘no that’s gross you are crazy he is just a kid’.

"I didn’t want to think it was happening."

But what frustrated the anonymous woman perhaps more than the incident itself, was her boyfriend's reaction.

"He says ‘there’s nothing I can do about it, I don’t have custody, he doesn’t know what he is doing, he doesn’t know any better’," she explained.

In her post, she detailed her partner's defensive behaviour, and said he didn't seem to care how she was feeling "about basically being used as a sex object by his child son."

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Now, her boyfriend is angry at her, but she insists "his son needs to learn these boundaries now that he is becoming a teenager."

"I also just feel really grossed out and violated and weird that I have been basically sexually assaulted by a child for several times over the past year," she wrote.

Other Reddit users offered their advice to the woman, with some saying she was "overreacting."

"I think you are overreacting when you say you were basically sexually assaulted by your boyfriend's son," read one comment. The anonymous user did, however, agree that her partner's behaviour wasn't good enough.

"I think your boyfriend is doing a disservice to his son by not talking to him about what he is doing though," they wrote. "I doubt his son understands what he is doing and needs to have it explained to him."

"The boy doesn't understand boundaries," said another user. "Next time tell him to cut it out. You're mad at a barely pubescent boy with downs syndrome? He probably barely understands why he wants to do it in the first place and doesn't understand that it's wrong."

What advice would you give this woman?