A man unwittingly sparked cheating accusations between his sister and brother-in-law after he sent the woman flowers anonymously to cheer her up.

"We talk regularly, and during one such conversation, she told me she’s been feeling really depressed/overwhelmed lately. As we were talking, I could tell she was holding back tears. So I decided to do something nice for her," he began on Reddit.

His solution was to have flowers delivered anonymously to her job, with a note that simply read: "Thinking of you."

After receiving the thoughtful gift, his sister called her husband and "thanked him for the flowers," but he told her he hadn’t sent anything and accused her of having an affair.

"A few hours later, the florist called me up and told me a man [brother-in-law] has been calling them non-stop and demanding they tell him who sent his wife flowers. They tried to explain that it was against their policy to reveal that information, but the man wouldn’t talk no for an answer. Apparently, he became so aggressive and threatening over the phone, the shop called me up and asked my permission to reveal the name of the sender to the man," he continued.

[Her husband] believed her affair partner had sent them to her, which is why he called the florist like a lunatic, demanding names. Now my sister is more depressed than ever and she’s been fighting with my brother-in-law ever since," the man concluded.

READ MORE: Woman Refuses to Let Sister, Brother-in-Law Move In After They Insist She ‘Make Space for Their Relationship’

Despite him thinking he was doing something nice, Reddit users in the comments section slammed him for not thinking the gesture all the way through.

"Why wouldn't you sign the card? That's just dumb. It's obvious your sister is in a borderline abusive relationship. Please tell me you've cleared this up since 'she's more depressed than ever,'" one person wrote.

"I am not sure how anyone thinks sending anonymous flowers to a married woman would end up well. You are 37. Old enough to know better. Sister thinks husband did a nice thing for her, turns out husband did not. Who did?! Why did you not sign the card?! Have you told them it was you? Husband is an all-around jerk for flying off the handle right away. Why assume wife/sister is having an affair right off the bat? I have a feeling sister is depressed because of him," another commented.

"Why would he think an anonymous love letter would cheer up a grown married woman and make her feel better? ...Weird. Flowers from my brother? I'd be thrilled. Flowers from an anonymous stranger? I'd be creeped the hell out," someone else weighed in.

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