You need to unbury them and show them to the mommy so she knows that they are in Heaven.

 You need to unbury them and show them to the mommy so she knows that they are in Heaven. Give her time to say goodbye. The suggestion of getting other kittens from shelters for her to nurse and mother is a great one. If you do this, let the kittens nurse for a full 12 weeks. It would be great if you could adopt two and then keep them. If you are not intending to keep them, be very careful when you place them because there are cruel people who are looking for kittens to abuse. After 12 weeks, take mommy in and get her spayed. Please keep her inside the house from now on so she’s safe. Cats are not safe outside. Please let me know by replying to this answer what you decide to do. But you must give your mother cat the opportunity to say goodbye to her kittens. And if you are not going to foster/adopt other kittens, immediately take her in and get her spayed. If you decide to adopt or foster kittens from a shelter, if you intend to keep them, I can give you other tips for caring for kittens.

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