Mum explains heartbreaking reason she has four triplets

One mum has shared the heartbreaking reason that she has "four triplets".

In a TikTok video, the US mum (whose name is not identified) shows her "four little triplets" sleeping peacefully, which confused commenters.

"Four triplets??? When there are triplets ain't (there) gonna be three of them?" one commenter asked. "Doesn't four mean quadruplets?" asked another.

Others thought to look closely at the mother's username, @mamato7_5here_2above.

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"For those that don't know the oldest sister is a triplet, her brother and sister passed, then mum had a second set of triplets - they're all triplets," explained one commenter.

The family also has one older son who was not part of a multiple and was born before the two sets of triplets.

Once people understood how there were four triplets, they were very sympathetic towards the mother.

"It's amazing how very much they all look alike coming from two sets of triplets. Bless her heart she must remember and they are her saving grace," said one commenter.

"As a triplet herself, there must be a strong subconscious ('muscle') memory to that energy. They are a beautiful gift for her as well," said another.

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In another video, the mum asks Lana, the oldest "triplet", the names of her triplet brother and sister. At first she names her baby triplet sibling's names, but once asked about her own, she is able to name them, "Milan" and "Katarina".

Commenters praised the mum's approach to the sensitive subject.

"The fact that she knows... I'm crying," said one commenter.

"It's amazing that you're raising them to be so aware of their siblings in heaven. It's beautiful," added another.