"I have 4 children. The oldest one is Olivia, 26, twins James and Henry, 22, and Emma, 17. I discovered that Emma wasn’t mine about 2-3 months after the birth," one man started in a confessional, posted to Reddit's "r/TrueOffMyChest."

The subreddit is an online forum where users can reveal personal things that have happened in their lives and essentially, get them off their chests.

He says he's being pressured to give money to a child that isn't his after paying child support for 18 years.

In his Reddit post, the 46-year-old man explains that he had an inkling that Emma wasn't his daughter after she was born and noticed she didn't look anything like him.

After several months went by, he decided to do a paternity test with his wife in the chance that their daughter may have been switched at the hospital.

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When the results finally came in, he found out that Emma wasn't his daughter, but was his wife's child, meaning she had an affair while they had been married.

Shortly after, he filed for divorce, and at the end of it, he got 50/50 custody of his twin sons and eldest daughter.

However, he was still required to pay child support for Emma.

"I tried to fight it with evidence that the kid wasn’t mine, but the court verdict was that she was legally mine so I had to pay it unless the father [of] the youngest one would show up and take responsibility," he revealed.

Since his ex-wife refused to tell anyone who Emma's father was, he had to pay child support for 18 years, but told his ex that he wouldn't be sending her money outside of that, and didn't want a relationship with Emma at all.

After the divorce was finalized, he moved to a different city to get a fresh start and tried to go to therapy to work through his trust issues that had formed after the entire debacle with his ex-wife.

"The main issue was I couldn’t trust anyone except for my kids and family, which mainly destroyed every single relationship," he added, noting that he tried to date but found it unsuccessful.

Eventually, his daughter, Olivia, came to live with him when she was 14 after getting into a fight with her mom and lived with him until she was 20.

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His ex-wife asked him whether Emma would be receiving money that he had put aside for his children.

He revealed that for his children, he had set aside a large sum of money for them.

"I tried to teach them to not waste money and invest, but [in] the end, it was up to them. Fortunately, they invested the money smartly and are currently living independently."

However, issues started after his ex-wife "started hinting" about when Emma would receive her money just as her siblings had.

"At first, I thought she was joking and jokingly said when her real father will appear. She got extremely angry and started yelling about how bad a father I’m and that joke was inappropriate," he recounted.

He rebutted, telling his ex-wife that he's already paid child support for the past 18 years and she should've thought better before cheating on him. He blocked her number shortly after.

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Emma eventually called him, asking why she wasn't receiving any of the money that he had set aside.

"I politely said that she knows that she isn’t my child, she got angry yelled that this wasn’t fair, and [hung] up."

Since their conversation, his ex-wife has continued to call him from different numbers, telling him that he's a "bad person."

While he can afford to give Emma money, at the same time, he doesn't want to.

"I [wish] Emma [and I] never had a relationship, maybe we would speak two or three times a year. At the same time, I feel guilty for excluding and punishing her for what my ex did," he concluded.

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Most Reddit users who commented on the man's post understood why he's hesitant to give a child that isn't his money.

"You have paid the child support that was court-ordered for a child that biologically isn't yours. You have made those payments in full," one user wrote.

"I'm sorry but you don't owe that child anything else, you didn't raise them, you just were forced to pay for them. Your ex can give them some money."

Another user added, "You supported Emma for 18 years. You’ve done enough. I might feel differently if you had raised her for 17 years than THEN found out she wasn’t yours."

"But you’ve stated that you never had a relationship with her, and you divorced her mom when she was just a few months old."

A third user remarked, "You were wronged. I know how upsetting, frustrating, infuriating, and annoying injustice can be."

"And although some people in society may dislike you for it, I see no harm in taking some personal justice in your hand, given the circumstances."

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Nia Tipton is a writer living in Brooklyn. She covers pop culture, social justice issues, and trending topics. Keep up with her on Instagram and Twitter.